Air conditioners

Abstract

To provide an air conditioner that can improve safety of the air conditioner using a combustible refrigerant.SOLUTION: An air conditioner according to the present disclosure uses a combustible refrigerant, and comprises a case constituting the appearance of an indoor unit, a heat exchanger housed in the case, a fan arranged inside the heat exchanger, a fan motor connected to the fan, and an electric component including a control circuit for centrally controlling the indoor unit. The heat exchanger comprises a plurality of heat transfer pipes extending from one end of the heat exchanger to the other end and turning back, and through which the combustible refrigerant flows, and brazed parts brazed to the plurality of heat transfer pipes on the side of the one end of the heat exchanger. The electric component and the fan motor are arranged on the side of the other end of the heat exchanger.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an air conditioner. [Background technology]

[0002] As an air conditioner, for example, Patent Document 1 discloses an air conditioner that uses a flammable refrigerant as a working refrigerant.

[0003] Patent Document 1 discloses an air conditioner that houses a heat exchanger that uses a flammable refrigerant as a working refrigerant and electrical equipment in a casing. The air conditioner described in Patent Document 1 is characterized in that the electrical equipment is disposed in the upper part of the casing so as to be positioned higher than the heat exchanger and offset to one side in the width direction of the heat exchanger. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3807004 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the air conditioner described in Patent Document 1 still has room for improvement in terms of improving the safety of air conditioners that use flammable refrigerants.

[0006] Therefore, an object of the present disclosure is to solve the above-mentioned problems and to provide an air conditioner that can improve the safety of air conditioners that use a flammable refrigerant. [Means for solving the problem]

[0007] An air conditioner of one embodiment of the present disclosure is an air conditioner that uses a flammable refrigerant and includes a housing that forms the exterior of the indoor unit, a heat exchanger housed within the housing, a fan arranged inside the heat exchanger, a fan motor connected to the fan, and electrical equipment including a control circuit that performs overall control of the indoor unit, wherein the heat exchanger extends from one end to the other end of the heat exchanger and turns back, and includes a plurality of heat transfer tubes through which the flammable refrigerant flows, and a brazing portion brazed to the plurality of heat transfer tubes at one end side of the heat exchanger, and the electrical equipment and fan motor are arranged on the other end side of the heat exchanger. Effect of the Invention

[0008] According to the present disclosure, it is possible to improve the safety of air conditioners that use flammable refrigerants. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of an air conditioner according to a first embodiment of the present disclosure. [Diagram 2] Schematic diagram of the internal structure of the indoor unit [Diagram 3] Schematic diagram of heat transfer tube and brazed part [Figure 4] Side view of indoor unit [Diagram 5] Schematic diagram of sensor-related components [Figure 6] Flowchart of air conditioner operation [Figure 7] Schematic diagram of the internal structure of the indoor unit of Modification 1 [Figure 8] FIG. 13 is a schematic diagram of an internal structure of an indoor unit according to a second embodiment of the present disclosure. [Figure 9] Schematic diagram of the isolation wall [Figure 10] Schematic diagram of the internal structure of the indoor unit of modified example 2 [Figure 11] Schematic diagram of the internal structure of the indoor unit of modified example 3 [Figure 12] Schematic diagram of the internal structure of the indoor unit of modified example 4 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (Background to this disclosure) An example of a refrigerant used in air conditioners is R32. The global warming potential (GWP) of R32 is 675, and from the perspective of preventing global warming, the use of refrigerants such as isobutane or propane, which have a lower global warming potential, has been proposed.

[0011] However, refrigerants such as isobutane or propane are flammable refrigerants. On the other hand, electrical equipment may generate ignition sources such as sparks. If a flammable refrigerant leaks into the indoor unit of an air conditioner and comes into contact with a spark or the like generated by the electrical equipment, the flammable refrigerant may ignite inside the indoor unit. The generated fire may further ignite the flammable refrigerant that has leaked into the room, causing damage to the user. Therefore, there is a demand for preventing the ignition of the flammable refrigerant inside the indoor unit and improving the safety of air conditioners that use flammable refrigerants.

[0012] Therefore, the inventors identified the brazed parts of the heat exchanger as the parts in the indoor unit that are prone to leaking flammable refrigerant, and discovered a configuration that prevents flammable refrigerant leaking from the brazed parts from reaching electrical equipment.

[0013] Based on these novel findings, the present inventors have made the following disclosure.

[0014] The air conditioner of a first aspect of the present disclosure is an air conditioner that uses a flammable refrigerant and includes a housing that forms the exterior of the indoor unit, a heat exchanger housed within the housing, a fan arranged inside the heat exchanger, a fan motor connected to the fan, and electrical equipment including a control circuit that performs overall control of the indoor unit, the heat exchanger extends from one end to the other end of the heat exchanger and turns back, and includes a plurality of heat transfer tubes through which the flammable refrigerant flows, and a brazing portion brazed to the plurality of heat transfer tubes at one end side of the heat exchanger, and the electrical equipment and the fan motor are arranged on the other end side of the heat exchanger.

[0015] With this configuration, by arranging the electrical equipment and fan motor away from the brazed parts, it is possible to prevent ignition of flammable refrigerant due to sparks generated by the electrical equipment and fan motor, thereby improving the safety of air conditioners that use flammable refrigerants.

[0016] In the air conditioner according to the second aspect of the present disclosure, the electrical components may be disposed at a position higher than the heat exchanger.

[0017] With this configuration, it is possible to prevent the flammable refrigerant, which is heavier than air, from reaching the electrical components through the brazed portions.

[0018] In the air conditioner of the third aspect of the present disclosure, a sensor is further provided that is arranged around the brazed portion and detects information about the flammable refrigerant, and the control circuit may have a processing unit that determines whether or not there is a leakage of the flammable refrigerant based on the information about the flammable refrigerant detected by the sensor.

[0019] With this configuration, leakage of flammable refrigerant in the air conditioner can be detected.

[0020] In the air conditioner of the fourth aspect of the present disclosure, the sensor may be disposed at a position lower than the brazed portion.

[0021] With this configuration, leakage of a flammable refrigerant that is heavier than air can be detected.

[0022] In the air conditioner according to the fifth aspect of the present disclosure, the processing unit may drive the fan motor depending on the result of the determination of leakage of the flammable refrigerant.

[0023] With this configuration, it is possible to prevent the leaked flammable refrigerant from forming a flammable region.

[0024] The air conditioner of the sixth aspect of the present disclosure may further include a communication unit that communicates the result of the determination of the flammable refrigerant leakage to an external device.

[0025] With this configuration, the result of the leakage determination can be transmitted from the air conditioner to another device.

[0026] The air conditioner according to the seventh aspect of the present disclosure may further include a notification unit that notifies the result of the determination of leakage of flammable refrigerant.

[0027] With this configuration, it is possible to notify the result of the leak determination.

[0028] The air conditioner according to the eighth aspect of the present disclosure may further include a partition wall that is disposed on the other end side of the heat exchanger within the housing and divides the inside of the housing.

[0029] With this configuration, it is possible to prevent flammable refrigerant leaking from the brazed parts inside the housing from reaching the electrical components.

[0030] (Embodiment 1) An air conditioner according to a first embodiment of the present disclosure will be described.

[0031] [Overall configuration] Fig. 1 is a schematic diagram showing an example of an air conditioner 1 according to a first embodiment of the present disclosure. As shown in Fig. 1, the air conditioner 1 includes an indoor unit 10 and an outdoor unit 20. The indoor unit 10 and the outdoor unit 20 are connected via a refrigerant pipe 50.

[0032] The indoor unit 10 includes a first heat exchanger 11, an indoor fan 12, an indoor fan motor 13, a sensor 17, a first electrical component 30, and part of the refrigerant piping 50. The indoor unit 10 is placed indoors.

[0033] The outdoor unit 20 includes a second heat exchanger 21, an outdoor fan 22, a compressor 23, an expansion mechanism 24, a four-way valve 25, a second electric component 40, and part of the refrigerant piping 50. The outdoor unit 20 is disposed outside the room.

[0034] The components of the indoor unit 10 will be described.

[0035] <1st heat exchanger> For example, during cooling operation, the first heat exchanger 11 exchanges heat with the air and evaporates the refrigerant flowing into the first heat exchanger 11. As described below, the first heat exchanger 11 includes fins, heat transfer tubes 15, and brazed parts 16. The fins are made of a plurality of thin metal plates, and are arranged so that the surfaces of the metal plates are parallel to each other. The heat transfer tubes 15 are arranged perpendicular to the surfaces of the fins and penetrate the fins. The heat transfer tubes 15 and the brazed parts 16 will be described in detail later.

[0036] <Indoor fan> The indoor fan 12 is disposed inside the first heat exchanger 11, and blows out toward the room the air whose temperature has been adjusted by the first heat exchanger 11. For example, the indoor fan 12 is a cross-flow fan.

[0037] <Indoor fan motor> The indoor fan motor 13 is connected to the indoor fan 12 and drives the indoor fan 12. The indoor fan motor 13 is disposed in the indoor unit 10 together with the indoor fan 12.

[0038] <Sensor> The sensor 17 detects information relating to the flammable refrigerant inside the indoor unit 10. The sensor 17 is disposed around the first heat exchanger 11. The sensor 17 will be described in detail later.

[0039] <First Electrical Component> The first electrical component 30 is composed of, for example, semiconductor elements. The first electrical component 30 includes a control circuit that performs overall control of the indoor unit 10. The first electrical component 30 includes a control board, a drive motor for a flap that covers the air outlet of the indoor unit 10, a cleaning motor for the indoor unit 10, etc. In addition, the first electrical component 30 is connected to the electronic circuit of the indoor unit 10 by a first electrical wiring 31.

[0040] <Refrigerant piping> The refrigerant piping 50 is disposed so as to connect the first heat exchanger 11, the compressor 23, the four-way valve 25, the second heat exchanger 21, and the expansion mechanism 24. For example, the refrigerant piping 50 connects the first heat exchanger 11, the compressor 23, the four-way valve 25, the second heat exchanger 21, and the expansion mechanism 24 in this order.

[0041] The refrigerant pipe 50 has a flow path through which the refrigerant flows inside the refrigerant pipe 50, and circulates the refrigerant. For example, the refrigerant pipe 50 has a hollow cylindrical shape.

[0042] A flammable refrigerant such as isobutane or propane is used as the working refrigerant of the air conditioner 1. The working refrigerant may be a single flammable refrigerant, or may be a mixed refrigerant of another type of refrigerant and a flammable refrigerant.

[0043] Next, the components of the outdoor unit 20 will be described.

[0044] <Second heat exchanger> For example, during cooling operation, the second heat exchanger 21 exchanges heat with the air and condenses the refrigerant flowing into the second heat exchanger 21. The second heat exchanger 21 further includes an outdoor fan 22 that blows the air, the temperature of which has been adjusted by the second heat exchanger 21, to the outside of the room.

[0045] <Compressor> The compressor 23 is connected to the first heat exchanger 11 and the four-way valve 25 by a refrigerant piping 50. The compressor 23 is used to compress the refrigerant that flows in from the refrigerant piping 50.

[0046] <Expansion mechanism> The expansion mechanism 24 is connected to the first heat exchanger 11 and the second heat exchanger 21 by the refrigerant piping 50. The expansion mechanism 24 is used to expand the refrigerant that has flowed in from the refrigerant piping 50. For example, the expansion mechanism 24 is an expansion valve.

[0047] <Four-way valve> The four-way valve 25 is connected to the compressor 23, the first heat exchanger 11, and the second heat exchanger 21 by refrigerant piping 50. During cooling operation, the four-way valve 25 sends the refrigerant flowing out of the compressor 23 to the second heat exchanger 21 along the refrigerant flow direction 51. On the other hand, the four-way valve 25 changes the refrigerant flow direction depending on the operation mode of the air conditioner 1 (cooling operation, heating operation).

[0048] <Second Electrical Equipment> The second electrical component 40 is configured, for example, by a semiconductor element, etc. The second electrical component 40 includes a control circuit that performs overall control of the outdoor unit 20. The second electrical component 40 is also connected to an electronic circuit of the outdoor unit 20 by a second electrical wiring 41.

[0049] Next, the indoor unit 10 will be described in more detail with reference to Figs. 2 to 4.

[0050] Fig. 2 is a schematic diagram showing the internal structure of the indoor unit 10. Fig. 3 is a schematic diagram of a heat transfer tube 15 and a brazed portion 16. Fig. 4 is a side view of the indoor unit 10.

[0051] As shown in FIG. 2, the indoor unit 10 includes a first heat exchanger 11, an indoor fan 12, an indoor fan motor 13, a housing 14, a sensor 17, and a first electrical component 30.

[0052] The housing 14 constitutes the external appearance of the indoor unit 10. In the first embodiment, the first heat exchanger 11, the indoor fan 12, the indoor fan motor 13, the sensor 17, and the first electrical component 30 are housed in the housing 14. Although not shown, the housing 14 has an outlet through which the indoor fan 12 blows air into the room. The housing 14 may be formed of resin such as plastic.

[0053] As described above, the first heat exchanger 11 is connected to the refrigerant pipe 50 and includes a plurality of heat transfer tubes 15 through which the flammable refrigerant flows, and the brazed portions 16 brazed to the plurality of heat transfer tubes.

[0054] The heat transfer tube 15 extends from one end P1 of the first heat exchanger 11 to the other end P2 and then turns back. In the first embodiment, the heat transfer tube 15 has a U-shaped bent shape at the other end P2 of the first heat exchanger 11. The portions of the heat transfer tube 15 that extend along the first heat exchanger 11 may be parallel to each other.

[0055] The heat transfer tube 15 has a flow path through which the refrigerant flows. For example, the heat transfer tube 15 has a hollow cylindrical shape similar to the refrigerant pipe 50. Inside the heat transfer tube 15, the refrigerant flowing into the first heat exchanger 11 is evaporated by heat exchange with the surrounding air via the fins during, for example, cooling operation.

[0056] The brazed portion 16 is a pipe that functions to connect the heat transfer tubes 15. The first heat exchanger 11 is provided with a plurality of brazed portions 16. The brazed portions 16 are brazed to and connected to the plurality of heat transfer tubes 15 at one end P1 of the first heat exchanger 11. The brazed portion 16 has a U-shaped bent shape so as to connect two heat transfer tubes 15 that extend along each other. As shown in FIG. 3, the end portions on the one end side of the adjacent heat transfer tubes 15 are inserted into the brazed portion 16 and fixed by brazing. Furthermore, the brazed portion 16 may be shorter than the heat transfer tubes 15 in the longitudinal direction of the first heat exchanger 11.

[0057] The flammable refrigerant is likely to leak from the brazed portion 16. If a through hole such as a pinhole is formed in the solder used to fasten the heat transfer tube 15 to the brazed portion 16, the flammable refrigerant will leak from the inside to the outside of the brazed portion 16 through the through hole. For example, the pinhole is formed by corrosion of the solder.

[0058] As shown in FIG. 2, the first electrical component 30 and the indoor fan motor 13 are arranged on the other end P2 side of the first heat exchanger 11 opposite to the brazed portion 16 in order to be separated from the brazed portion 16. The "other end P2 side" of the first heat exchanger 11 means a position closer to the other end P2 than the center of the first heat exchanger 11. With this configuration, it is possible to prevent the flammable refrigerant leaking from the brazed portion 16 from reaching the first electrical component 30 and the indoor fan motor 13, thereby improving the safety of the air conditioner 1. The first electrical component 30 and the indoor fan motor 13 may be separated from the other end P2 of the first heat exchanger 11 and have a gap between them. In addition, the indoor fan motor 13 may be arranged closer to the first heat exchanger 11 than the first electrical component 30, or may be arranged coaxially with the indoor fan 12.

[0059] Furthermore, the air conditioner 1 has a power supply wiring 32 that electrically connects the outdoor unit 20 and the first electrical component 30. As shown in FIG. 4, the indoor unit 10 is attached to the indoor surface of a wall K of a building, and the power supply wiring 32 is arranged on the outside of the housing 14. The power supply wiring 32 may be arranged along the back surface of the housing 14 that faces the wall K. The power supply wiring 32 also extends from the indoor side to the outdoor side of the wall K. Although not shown, a through hole may be provided in the wall K, and the refrigerant piping 50 and the power supply wiring 32 may be passed through the through hole to the outside of the room. With this configuration, the number of through holes provided in the wall K can be reduced.

[0060] Returning to Fig. 2, the sensor 17 will be described. The sensor 17 may detect the flow rate or concentration of the flammable refrigerant as the information on the flammable refrigerant. Alternatively, the sensor 17 may detect the presence or absence of the flammable refrigerant. The sensor 17 is, for example, an infrared sensor, a semiconductor sensor, or a catalytic combustion sensor.

[0061] The sensor 17 is disposed around the brazed portion 16. Thus, the sensor 17 may detect information about the flammable refrigerant leaking from the brazed portion 16. In addition, the sensor 17 may detect information about the flammable refrigerant leaking from another portion of the first heat exchanger 11 or the refrigerant pipe 50. As shown in FIG. 2, in the first embodiment, the sensor 17 is disposed at a position lower than the brazed portion 16. The sensor 17 may be disposed at a position lower than the brazed portion 16A, which is located at a position where the distance between the inner wall on the bottom surface of the housing 14 and the brazed portion 16 is the shortest. The sensor 17 may be disposed in the housing 14 directly below the brazed portion 16, or may be disposed on a side surface of the housing 14 below the brazed portion 16. Furthermore, the sensor 17 may be directly attached to the brazed portion 16A on the refrigerant outflow side.

[0062] The sensor 17 will be described in more detail with reference to FIG.

[0063] 5 is a schematic diagram illustrating components related to the sensor 17 in the indoor unit 10. For convenience, part of the configuration of the indoor unit 10 is omitted.

[0064] 5, the sensor 17 is electrically connected to a control circuit included in the first electrical component 30. Specifically, the sensor 17 is electrically connected to a processing unit 33 in the control circuit. Furthermore, the processing unit 33 is electrically connected to a communication unit 34 in the control circuit.

[0065] The elements constituting the processing unit 33 may, for example, include a memory (not shown) that stores a program that causes these elements to function, and a processing circuit (not shown) corresponding to a processor such as a CPU (Central Processing Unit), and the processor may execute the program to function as these elements.

[0066] The processing unit 33 determines whether a flammable refrigerant leaks based on the information on the flammable refrigerant detected by the sensor 17. For example, when the sensor 17 detects the concentration of the flammable refrigerant, the processing unit 33 determines that a flammable refrigerant leak has occurred in the indoor unit 10 when the concentration of the flammable refrigerant exceeds a certain threshold value.

[0067] Although not shown, the processing unit 33 is further connected to the indoor fan motor 13. As will be described in detail later, the processing unit 33 drives the indoor fan motor 13 depending on the result of the determination of the leakage of the flammable refrigerant.

[0068] The communication unit 34 communicates the result of the flammable refrigerant leakage determination to an external device independent of the air conditioner 1. The leakage determination result is, for example, the flow rate, concentration, or presence or absence of the flammable refrigerant. The external device has a display unit 35, which displays the flammable refrigerant leakage determination result determined by the processing unit 33. The display unit 35 is, for example, a display.

[0069] The communication unit 34 conforms to a predetermined communication standard (for example, LAN, Wi-Fi (registered trademark), Bluetooth (registered trademark)) and includes a circuit for communicating with the display unit 35 of an external device. For example, the display of the remote controller of the air conditioner 1 may function as the display unit 35. The air conditioner 1 transmits information on the leak determination result to the remote controller via the communication unit 34. The remote controller may receive information on the leak determination result via the communication unit 34 and display the leak determination result on the display of the remote controller. Also, the display of a smartphone may function as the display unit 35. Specifically, the communication unit 34 of the air conditioner 1 and the smartphone may communicate with each other and the leak determination result may be displayed on the smartphone. For example, an application compatible with the air conditioner 1 may be provided on the smartphone, and the leak determination result may be displayed on the smartphone via the application.

[0070] [Operation] Next, an example of the operation of the air conditioner 1 will be described in detail with reference to Fig. 6. Fig. 6 is a flowchart of the operation of the air conditioner 1.

[0071] As shown in FIG. 6, the sensor 17 detects and acquires information related to the flammable refrigerant (S11).

[0072] Next, based on the information about the flammable refrigerant detected by the sensor 17, the processing unit 33 determines whether or not a leakage of the flammable refrigerant has occurred (S12).

[0073] If no leakage is occurring (No in S12), the process returns to S11, and the sensor 17 detects information regarding the flammable refrigerant.

[0074] If leakage has occurred (Yes in S12), the processing unit 33 drives the indoor fan motor 13 (S13). Driving the indoor fan motor 13 causes the indoor fan 12 to blow air. The air blown by the indoor fan 12 moves the flammable refrigerant from inside the indoor unit 10 to outside the indoor unit 10. Therefore, in the indoor unit 10, the flammable refrigerant is diluted, and it is possible to prevent the formation of a localized high concentration region of the flammable refrigerant. In other words, it is possible to prevent the flammable refrigerant from forming a flammable region.

[0075] The driving time, rotation speed, or other information related to the driving of the indoor fan motor 13 in S13 may be stored in advance in the processing unit 33. The driving time, rotation speed, and air blowing direction of the indoor fan 12 of the indoor fan motor 13 may be set depending on the amount and type of flammable refrigerant in the air conditioner 1 and the area of ​​the room in which the air conditioner 1 is installed. The air blowing direction of the indoor fan 12 may be set to upward.

[0076] Furthermore, in S13, among the electronic components of the first electrical component 30, electronic components other than the electronic components related to driving the indoor fan motor 13 may be stopped. This makes it possible to prevent the first electrical component 30 from generating sparks or the like that could be an ignition source for the flammable refrigerant.

[0077] Next, the display unit 35 displays the result of the determination by the processing unit 33 (S14).

[0078] Note that the display unit 35 may display the result of the determination made by the processing unit 33 even if no leakage has occurred (No in S12).

[0079] [effect] According to the air conditioner 1 according to the first embodiment, the following effects can be achieved.

[0080] The air conditioner 1 uses a flammable refrigerant. The air conditioner 1 includes a housing 14, a first heat exchanger 11, an indoor fan 12, an indoor fan motor 13, and a first electrical component 30. The housing 14 constitutes the exterior of the indoor unit 10. The first heat exchanger 11 is accommodated in the housing 14. The indoor fan 12 is disposed inside the first heat exchanger 11. The indoor fan motor 13 is connected to the indoor fan 12. The first electrical component 30 includes a control circuit that comprehensively controls the indoor unit 10. The first heat exchanger 11 includes a plurality of heat transfer tubes 15 and a brazed portion. The plurality of heat transfer tubes 15 extend from one end P1 of the first heat exchanger 11 to the other end P2, turn back, and a flammable refrigerant flows inside the first heat exchanger 11. The brazed portion is brazed to the heat transfer tube 15 on the one end P1 side of the first heat exchanger 11. The first electrical component 30 and the indoor fan motor 13 are disposed on the other end P2 side of the first heat exchanger 11.

[0081] With this configuration, the first electrical component 30 and the indoor fan motor 13 are disposed away from the brazed portion 16 from which flammable refrigerant is likely to leak, preventing sparks and the like generated from the first electrical component 30 and the indoor fan motor 13 from becoming an ignition source. This prevents ignition of the flammable refrigerant and improves the safety of the air conditioner 1 that uses a flammable refrigerant.

[0082] The air conditioner 1 further includes a sensor 17 that is disposed around the brazed portion 16 and detects information related to the flammable refrigerant. The control circuit has a processing unit 33 that determines whether or not there is a leakage of the flammable refrigerant based on the information related to the flammable refrigerant detected by the sensor 17.

[0083] With this configuration, leakage of flammable refrigerant in the air conditioner 1 can be detected and determined.

[0084] The sensor 17 is disposed at a position lower than the brazed portion 16 .

[0085] With this configuration, the sensor 17 can detect leakage of a flammable refrigerant that is heavier than air.

[0086] The processing unit 33 drives the indoor fan motor 13 according to the result of the determination of the leakage of the flammable refrigerant.

[0087] With this configuration, it is possible to prevent the leaked flammable refrigerant from forming a flammable region due to the air blown by the indoor fan 12 driven by the indoor fan motor 13.

[0088] The air conditioner 1 has a communication unit 34, and the communication unit 34 communicates the result of the determination of the leakage of the flammable refrigerant to an external device.

[0089] With this configuration, the result of the determination of a flammable refrigerant leak can be communicated to the user of the air conditioner 1. This allows the user to take appropriate measures against the flammable refrigerant leak, such as ventilating the room or evacuating, thereby improving the safety of the air conditioner 1.

[0090] The first heat exchanger 11 may be referred to as a "heat exchanger", the indoor fan 12 as a "fan", the indoor fan motor 13 as a "fan motor", and the first electrical component 30 as an "electrical component".

[0091] Although an example has been described in which the first electrical component 30 and the indoor fan motor 13 are disposed away from the other end P2 of the first heat exchanger 11, the present invention is not limited to this. It is sufficient that the first electrical component 30 and the indoor fan motor 13 are disposed closer to the other end P2 than near the center of the first heat exchanger 11. Even with this configuration, the first electrical component 30 and the indoor fan motor 13 can be disposed away from the brazed portion 16.

[0092] Although an example in which one end of the heat transfer tube 15 is inserted into the brazed portion 16 and fixed has been described, the present invention is not limited to this. The brazed portion 16 may be inserted into the end of one end of the heat transfer tube 15.

[0093] Although the example in which the heat transfer tube 15 and the brazed portion 16 are bent into a U-shape has been described, the present invention is not limited to this.

[0094] Although the example in which the first electrical component 30 is disposed farther from the first heat exchanger 11 than the indoor fan motor 13 has been described, the present invention is not limited to this. The first electrical component 30 may be disposed closer to the first heat exchanger 11 than the indoor fan motor 13.

[0095] Although the example in which the sensor 17 is disposed at a position lower than the brazed portion 16 has been described, the present invention is not limited to this. For example, when a flammable refrigerant that is lighter than air is used as the working refrigerant, the sensor 17 may be disposed at a position higher than the brazed portion 16.

[0096] Although an example in which the indoor unit 10 has one sensor 17 has been described, the present invention is not limited to this. For example, the indoor unit 10 may be provided with a plurality of sensors 17. The plurality of sensors 17 may detect different types of information related to the flammable refrigerant. Furthermore, the sensor 17 may be provided not only on one end P1 side of the first heat exchanger 11 but also on the center or other end P2 side of the first heat exchanger 11.

[0097] Although an example in which the processing unit 33 is connected to the indoor fan motor 13 has been described, the present invention is not limited to this.

[0098] Although an example in which the display unit 35 is a display on an external device has been described, the present invention is not limited to this. The display unit 35 may be a display that is disposed on the outside of the housing 14 of the indoor unit 10 and connected to the processing unit 33. In addition, the display unit 35 is not limited to a display, and may be an LED that lights up according to the result of the determination of the leakage of the flammable refrigerant.

[0099] Although the display unit 35 is a display, the display unit 35 is not limited to this. For example, the display unit 35 is an alarm unit that notifies the result of the determination of the leakage of the flammable refrigerant, and a control circuit that controls the alarm unit. The alarm unit may notify the result of the determination of the leakage by emitting a sound. For example, when the processing unit 33 determines that there is a leakage of the flammable refrigerant, the processing unit 33 transmits a signal to the control circuit of the display unit 35. When the control circuit receives a signal from the processing unit 33, the control circuit makes the alarm unit sound. The alarm unit is disposed in a position where the user of the air conditioner 1 can hear it. For example, the alarm unit is disposed outside the housing 14 of the indoor unit 10. Even with such a configuration, the user of the air conditioner 1 can be notified of the result of the determination of the leakage of the flammable refrigerant, and the safety of the air conditioner 1 can be improved.

[0100] Although an example in which the first electrical component 30 is disposed inside the housing 14 of the indoor unit 10 has been described, the present invention is not limited to this. For example, as in Modification 1 described later, the first electrical component 30 may be disposed outside the indoor unit 10 at a position higher than the first heat exchanger 11.

[0101] (Variation 1) Fig. 7 is a schematic diagram of the indoor unit 10 of Modification 1. As shown in Fig. 7, the first electrical component 30 is disposed on the upper surface of the housing 14, outside the housing 14 of the indoor unit 10. The first electrical component 30 is disposed on the upper surface of the housing 14, on the other end P2 side of the first heat exchanger 11.

[0102] Furthermore, the first electrical component 30 may be covered with a cover that protects electronic components of the first electrical component 30. The first electrical component 30 may have wiring connected to the indoor fan motor 13. The wiring may pass through the housing 14.

[0103] With this configuration, the outer wall of the housing 14 is located between the first electrical component 30 and the brazed portion 16. This prevents flammable refrigerant leaking from the brazed portion 16 inside the housing 14 from reaching the first electrical component 30, and further prevents sparks and the like generated by the first electrical component 30 from becoming an ignition source.

[0104] Although the example in which the first electrical component 30 is disposed on the other end P2 side of the first heat exchanger 11 has been described, the present invention is not limited to this. The first electrical component 30 may be disposed on the other end P2 side from the center of the first heat exchanger 11.

[0105] (Embodiment 2) An air conditioner 1A according to embodiment 2 of the present disclosure will be described. Note that in embodiment 2, differences from embodiment 1 will be mainly described. In embodiment 2, configurations that are the same as or equivalent to embodiment 1 will be described with the same reference numerals. Also, in embodiment 2, descriptions that overlap with embodiment 1 will be omitted.

[0106] 8 is a schematic diagram of the internal structure of an indoor unit 10A according to a second embodiment of the present disclosure. For the sake of simplicity, part of the configuration of the air conditioner 1A, including the sensor 17, is omitted.

[0107] The second embodiment differs from the first embodiment in that the indoor unit 10A has a partition wall 18. In other respects than those described above, the air conditioner 1A according to the second embodiment has a similar structure to the air conditioner 1.

[0108] The partition wall 18 serves to divide the interior of the housing 14. In the second embodiment, the partition wall 18 is disposed within the housing 14 and divides the interior of the housing 14 into a first space R1 and a second space R2. The outer periphery of the partition wall 18 is in contact with the inner wall of the housing 14. The partition wall 18 extends from the inner wall of the front side of the housing 14, contacting and following the upper and lower surfaces of the housing 14, to the inner wall of the rear side of the housing 14.

[0109] Here, the end of the housing 14 on one end P1 side of the first heat exchanger 11 is referred to as the first end Q1, and the end of the housing 14 on the other end P2 side is referred to as the second end Q2. The first space R1 is defined by the partition wall 18 and the inner wall of the housing 14 on the second end Q2 side. On the other hand, the second space R2 is defined by the partition wall 18 and the inner wall of the housing 14 on the first end Q1 side. The first electrical component 30 and the indoor fan motor 13 are disposed in the first space R1, and the brazed portion 16 is disposed in the second space R2. In other words, the partition wall 18 is disposed between the first electrical component 30 and the indoor fan motor 13 and the brazed portion 16. With this configuration, the partition wall 18 can suppress the movement of flammable refrigerant leaking from the brazed portion 16 from the second space R2 to the first space R1, thereby improving the safety of the air conditioner 1A.

[0110] 8, the partition wall 18 is disposed on the other end P2 side of the first heat exchanger 11, and the first heat exchanger 11 is disposed in the second space R2. The partition wall 18 may be disposed away from the first heat exchanger 11 so as to have a gap between the partition wall 18 and the first heat exchanger 11.

[0111] The structure of the isolation wall 18 will be described in more detail with reference to FIG.

[0112] FIG. 9 is a schematic diagram of the partition wall 18. As shown in FIG.

[0113] 9, the partition wall 18 is a plate-like member. The partition wall 18 may be a plate-like member having a thickness of 3 mm or more.

[0114] The upper and lower parts of the partition wall 18 are made of different materials. The upper part of the partition wall 18 is made of a material having a plurality of openings. On the other hand, a through hole may be formed in the lower part of the partition wall 18. The shaft of the indoor fan motor 13 connected to the rotating shaft of the indoor fan 12 penetrates and closes the through hole. With this configuration, air can move from the first space R1 to the second space R2, while the movement of the flammable refrigerant that is heavier than air is suppressed. For example, the upper part of the partition wall 18 is made of a mesh member 19 having a plurality of through holes formed therein.

[0115] The interval between the openings formed by the mesh member 19 may be equal to or less than the quenching distance D1 of the flammable refrigerant. The quenching distance D1 according to the electric charge spark method is calculated by the following formula (1) using the minimum energy E of the flammable refrigerant. D1 = 0.35E / 2 (1) The minimum energy E is the energy required for a flammable refrigerant to be ignited by an electric spark. For example, when the flammable refrigerant is propane, the minimum energy of propane is 0.3 mJ or more and 0.7 mJ or less. Therefore, the quenching distance D1 of propane is 2 mm. To suppress the flame propagation of propane, the spacing between the openings of the mesh member 19 may be set to 2 mm or less.

[0116] The mesh member 19 is made of metal. The mesh member 19 is made of, for example, steel. The lower part of the partition wall 18 may also be made of metal. On the other hand, the lower part of the partition wall 18 may be made of resin such as plastic. With such a structure, it is possible to reduce the weight of the indoor unit 10A.

[0117] Furthermore, the upper part of the isolation wall 18 may be formed of a punched metal instead of the mesh member 19. The punched metal is a metal plate member having a plurality of openings formed by press working using a die. The shape of the openings may be circular. Furthermore, the diameter of the openings may be equal to or smaller than the quenching diameter D2 of the flammable refrigerant. The quenching diameter D2 according to the electric charge spark method is calculated by the following formula (2) using the quenching distance D1. D2 = D1 / 0.7 (2) The quenching diameter D2 of propane is 3 mm. In order to suppress the flame propagation of propane, the diameter of the opening of the punched metal may be set to 3 mm or less.

[0118] [effect] According to the air conditioner 1A according to the second embodiment, the following effects can be achieved.

[0119] The air conditioner 1A uses a flammable refrigerant. The air conditioner 1A includes a housing 14, a first heat exchanger 11, an indoor fan 12, an indoor fan motor 13, a first electrical component 30, and a partition wall 18. The housing 14 constitutes the exterior of the indoor unit 10A. The first heat exchanger 11 is accommodated in the housing 14. The indoor fan 12 is disposed inside the first heat exchanger 11. The indoor fan motor 13 is connected to the indoor fan 12. The first electrical component 30 includes a control circuit that comprehensively controls the indoor unit 10A. The partition wall 18 is disposed in the housing 14 and divides the interior of the housing 14 into a first space R1 and a second space R2. The first heat exchanger 11 includes a plurality of heat transfer tubes 15 and a brazed portion. The plurality of heat transfer tubes 15 extend from one end P1 to the other end P2 of the first heat exchanger 11 and turn back, and a flammable refrigerant flows inside them. The brazed portion is brazed to the heat transfer tubes 15 on the one end P1 side of the first heat exchanger 11. The first electrical component 30 and the indoor fan motor 13 are disposed in the first space R1, and the brazed portion 16 is disposed in the second space R2.

[0120] With this configuration, inside the housing 14, the separating wall 18 can prevent the flammable refrigerant leaking from the brazed parts 16 from reaching the first electrical component 30 and the indoor fan motor 13. Sparks and the like generated from the first electrical component 30 and the indoor fan motor 13 can be prevented from becoming an ignition source. This prevents the flammable refrigerant from igniting, improving the safety of the air conditioner 1A that uses a flammable refrigerant.

[0121] The partition wall 18 is disposed on the other end P2 side of the first heat exchanger 11. The first heat exchanger 11 is disposed in the second space R2.

[0122] With this configuration, even if a flammable refrigerant leaks from the heat transfer tube 15, the flammable refrigerant can be prevented from reaching the first electric component 30 and the indoor fan motor 13.

[0123] The partition wall 18 has a plurality of openings formed in its upper portion.

[0124] With this configuration, even if a flammable refrigerant explodes in the first space R1, the pressure of the explosion can be released to the outside of the first space R1 through the opening, thereby preventing damage to the housing 14 that defines the first space R1 and reducing damage to people in the room.

[0125] The upper part of the separation wall 18 is formed of a mesh member 19 .

[0126] With this configuration, even if a flammable refrigerant causes an explosion in the first space R1, the pressure of the explosion can be further released through the mesh member 19 to the outside of the first space R1.

[0127] The mesh member 19 is made of metal.

[0128] With this configuration, the durability of the upper part of the partition wall 18 can be improved.

[0129] The spacing between the openings formed by the mesh member 19 is equal to or less than the quenching distance D1 of the flammable refrigerant.

[0130] With this configuration, even if an explosion occurs in the first space R1, the flame propagation can be suppressed.

[0131] The indoor fan motor 13 has a shaft connected to the rotation shaft of the indoor fan 12. A through hole through which the shaft passes is formed in the lower part of the isolation wall 18.

[0132] With this configuration, the indoor fan 12 can be driven while the indoor fan motor 13 is disposed in the first space R1 so as to improve the safety of the air conditioner 1A that uses a flammable refrigerant.

[0133] In the second embodiment, an example in which the upper part of the partition wall 18 is formed of the mesh member 19 has been described, but the present invention is not limited to this. For example, the partition wall 18 may be formed of a member that does not have any openings in its entirety. Also, as in Modification 2 described later, one opening may be formed in the upper part of the partition wall 18.

[0134] (Variation 2) Fig. 10 is a schematic diagram of the internal structure of an indoor unit 10A of Modification 2. As shown in Fig. 10, the upper part of the partition wall 18 is formed of a material having one opening. The opening may have a height of 1 / 6 to 1 / 3 of the height of the partition wall 18.

[0135] Even with this configuration, if the flammable refrigerant causes an explosion in the first space R1, the pressure of the explosion can be released to the outside of the first space R1 through the opening.

[0136] Although an example has been described in which the upper portion of partition wall 18 is formed from a material having one opening, the present invention is not limited to this. Instead of being formed from a material having an opening, partition wall 18 may not contact the upper surface of housing 14, and a gap may be formed between the upper end of partition wall 18 and the upper surface of housing 14. The height of the gap may be 1 / 6 or more and 1 / 3 or less of the height of partition wall 18.

[0137] In the second embodiment, the partition wall 18 is disposed on the other end P2 side of the first heat exchanger 11, but the present invention is not limited to this. For example, as in Modifications 3 and 4 described below, the partition wall 18 may be disposed on the one end P1 side of the first heat exchanger 11.

[0138] (Variation 3) Fig. 11 is a schematic diagram of the internal structure of the indoor unit 10A of Modification 3. As shown in Fig. 11, the partition wall 18 is disposed in the first heat exchanger 11 on the inner side of the brazed portion 16. For example, the partition wall 18 is disposed on one end P1 side of the first heat exchanger 11 so that the heat transfer tube 15 penetrates the partition wall 18. The first electrical component 30, the indoor fan motor 13, and part of the first heat exchanger 11 excluding the brazed portion 16 are disposed in the first space R1. Part of the heat transfer tube 15 and the brazed portion 16 are disposed in the second space R2.

[0139] Even with this configuration, the separating wall 18 can prevent the flammable refrigerant leaking from the brazed portion 16 from reaching the first electrical component 30 and the indoor fan motor 13. In addition, since the leaked flammable refrigerant does not flow out from the second space R2, it becomes easy to detect the leaked flammable refrigerant by a sensor or the like arranged in the second space R2.

[0140] The partition wall 18 may also serve as the fins of the first heat exchanger 11. The partition wall 18 may also serve as a flange for positioning the first heat exchanger 11 within the housing 14.

[0141] In the second embodiment, the first electrical component 30 and the indoor fan motor 13 are disposed on the other end P2 side of the first heat exchanger 11, but the present invention is not limited to this. For example, as in Modification 4 described below, the first electrical component 30 and the indoor fan motor 13 may be disposed on the one end P1 side of the first heat exchanger 11.

[0142] (Variation 4) Fig. 12 is a schematic diagram of the internal structure of the indoor unit 10A of the fourth modified example. As shown in Fig. 12, the partition wall 18 is disposed on one end P1 side of the first heat exchanger 11. In this case, the first space R1 is defined by the partition wall 18 and the inner wall of the housing 14 on the first end Q1 side. On the other hand, the second space R2 is defined by the partition wall 18 and the inner wall of the housing 14 on the second end Q2 side. The first electrical component 30 and the indoor fan motor 13 are disposed in the first space R1. The first heat exchanger 11 is disposed in the second space R2.

[0143] Even with this configuration, the partition wall 18 can prevent the flammable refrigerant leaking from the brazed portion 16 from reaching the first electrical component 30 and the indoor fan motor 13.

[0144] Although the present disclosure has been fully described in connection with the preferred embodiments with reference to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art, and such changes and modifications should be understood to be included within the scope of the present invention as defined by the appended claims, unless they depart therefrom. [Industrial Applicability]

[0145] INDUSTRIAL APPLICABILITY The air conditioner of the present disclosure is useful as an air conditioner because it can improve the safety of air conditioners that use flammable refrigerants. [Explanation of symbols]

[0146] 1. Air conditioner 10 Indoor unit 11 1st heat exchanger 12 Indoor fan 13 Indoor fan motor 14. Chassis 15 Heat transfer tube 16 Brazed part 17 Sensors 18 Isolation Wall 19 Mesh material 20 Outdoor unit 21 Second heat exchanger 22 Outdoor fan 23 Compressor 24 Expansion Mechanism 25 Four-way valve 30 First Electrical Equipment 31 First Electrical Wiring 32 Power wiring 33 Processing section 34 Communications Department 35 Display section 40 Second Electrical Equipment 41 Second electrical wiring 50 Refrigerant piping 51 Flow direction P1 one end P2 other end R1 First space R2 2nd space

Claims

1. An air conditioner using a flammable refrigerant, A housing that constitutes the exterior of the indoor unit; A heat exchanger housed within the housing; and A fan disposed inside the heat exchanger; a fan motor connected to the fan; An electrical component including a control circuit that comprehensively controls the indoor unit; Equipped with The heat exchanger includes: A plurality of heat transfer tubes extending from one end to the other end of the heat exchanger and turning back, through which the flammable refrigerant flows; a brazing portion brazed to the heat transfer tubes at the one end of the heat exchanger; Equipped with the electrical equipment and the fan motor are disposed on the other end side of the heat exchanger, The fan motor is arranged alongside the electrical equipment in an axial direction of the fan motor and closer to the heat exchanger than the electrical equipment.

2. The air conditioner according to claim 1 , wherein the electrical components are disposed at a position higher than the heat exchanger.

3. A sensor is further provided around the brazed portion to detect information about the flammable refrigerant.

3. The air conditioner according to claim 1, wherein the control circuit has a processing section that determines whether or not the flammable refrigerant is leaking based on information about the flammable refrigerant detected by the sensor.

4. The air conditioner according to claim 3 , wherein the sensor is disposed at a position lower than the brazed portion.

5. The air conditioner according to claim 3 or 4, wherein the processing unit drives the fan motor in response to a result of the determination of leakage of the flammable refrigerant.

6. The air conditioner according to claim 3 , further comprising a communication unit that communicates the result of the determination of the flammable refrigerant leakage to an external device.

7. The air conditioner according to claim 3 , further comprising a notification unit that notifies a result of the determination of leakage of the flammable refrigerant.

8. The air conditioner according to claim 1 , further comprising a partition wall disposed inside the housing on the other end side of the heat exchanger to separate an interior of the housing.

9. The air conditioner according to claim 3 , wherein the sensor is attached to the brazed portion.

10. The air conditioner according to claim 5 , wherein the processing unit stops electronic components of the electrical equipment other than electronic components related to driving the fan motor.

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