AIR CONDITIONING

Description

BACKGROUND1. Technical Field

[0001] The present invention relates to an air conditioner including a refrigeration cycle using a flammable refrigerant made of propane (R 290), isobutane (R 600a), ethane (R 170), and the like.2. Description of the Related Art

[0002] PTL 1 discloses an air conditioner including a sensor that detects a refrigerant leak, a heat exchange chamber, a machine chamber, and a drain pan extending from a lower part of the heat exchange chamber to a lower part of the machine chamber. The sensor is disposed near the drain pan. The refrigerant leaking from a heat exchanger flows along the drain pan and is detected by the sensor. The refrigerant leaking from a refrigerant pipe disposed in the machine chamber flows toward the lower part of the machine chamber, and is similarly detected by the sensor.

[0003] PTL 2 describes an air conditioner using a combustible HFC refrigerant.Citation ListPatent Literature

[0004] PTL 1: Unexamined Japanese Patent Publication No. 2002-098346 PTL 2: Unexamined Japanese Patent Publication No. 2016-080220 SUMMARY

[0005] An indoor unit of a wall-hung type includes a pipe connector that connects a refrigerant pipe attached to an indoor heat exchanger to a refrigerant pipe attached to an outdoor heat exchanger. When the indoor unit is installed by a left-hand pipe connection method, the pipe connector is located between the back of the indoor unit and the wall surface. The left-hand pipe connection method is a pipe connection method by which the refrigerant pipe is led into the indoor unit through a pipe attachment hole formed on the left side of the indoor unit. When the refrigerant leaks from the pipe connector, a leak detection sensor disposed in the indoor unit is unable to detect the refrigerant leak, which is a problem.

[0006] The present invention has been made in view of the above circumstances, and provides an air conditioner that can detect a refrigerant leak even when the refrigerant leak occurs between the back of an indoor unit and the wall surface.

[0007] An air conditioner according to the present invention is defined by the appended claims. It includes: an indoor heat exchanger in an indoor unit; an outdoor heat exchanger in an outdoor unit; a pipe connector connecting a refrigerant pipe attached to the indoor heat exchanger to a refrigerant pipe attached to the outdoor heat exchanger; and a flammable refrigerant filling each of the refrigerant pipes. In the air conditioner, the indoor unit includes: an air blow circuit housing the indoor heat exchanger; an underframe; a pipe connection housing section located on a back surface of the underframe of the indoor unit, the pipe connection housing section housing the pipe connector; and a leak detection sensor that detects a leak of the flammable refrigerant, the leak detection sensor being disposed in the air blow circuit, and the indoor unit further includes a communication path communicatively connecting the air blow circuit to the pipe connection housing section.

[0008] According to the air conditioner of the present invention, when the indoor unit of a wall-hung type is installed by a left-hand pipe connection method and the flammable refrigerant leaks from the pipe connector in such an installation condition, the flammable refrigerant flows through the communication path to reach the leak detection sensor in the air blow circuit. The air conditioner is, therefore, able to detect a refrigerant leak from the pipe connector, thus offering high safety at the occurrence of a refrigerant leak.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a schematic side view of an internal configuration of an indoor unit of an air conditioner according to a first exemplary embodiment; and FIG. 2 is a schematic front view of an internal configuration of an indoor unit of an air conditioner according to a second exemplary embodiment. DETAILED DESCRIPTION

[0010] Exemplary embodiments will now be described in detail with reference to the drawings. It should be noted that excessively detailed description may be skipped. For example, detailed description of known matters or duplicated description of substantially identical configurations may be avoided.

[0011] The accompanying drawings and the following description are provided to allow those skilled in the art to sufficiently understand the present disclosure, and are not intended to limit the subject matter described in the claims.(First exemplary embodiment)

[0012] FIG. 1 is a schematic side view of an internal configuration of indoor unit 100 of an air conditioner according to a first exemplary embodiment of the present invention. The first exemplary embodiment will hereinafter be described with reference to FIG. 1.

[0013] The air conditioner according to the present exemplary embodiment is an air conditioner using a flammable refrigerant gas, e.g., a flammable refrigerant made of propane (R 290), isobutane (R 600a), ethane (R 170), or the like.

[0014] Indoor unit 100 of the air conditioner according to the present exemplary embodiment includes indoor heat exchanger 101, a blower fan, machine chamber 106, underframe 103, and outer panel 104.

[0015] Indoor heat exchanger 101 is connected to an outdoor heat exchanger, a compressor, and a throttle device that are included in an outdoor unit, via refrigerant pipes. A refrigerant pipe attached to indoor heat exchanger 101 and a refrigerant pipe attached to the outdoor heat exchanger are connected to each other by pipe connector 102. The refrigerant pipe attached to the outdoor heat exchanger is connected to the outdoor unit via outdoor unit connection 109.

[0016] Machine chamber 106 houses a fan motor, a control board that controls indoor unit 100, and the like.

[0017] Indoor heat exchanger 101, the blower fan, and machine chamber 106 are placed in underframe 103. Underframe 103 includes air blow circuit 108 housing the blower fan and indoor heat exchanger 101, and pipe connection housing section 107 housing pipe connector 102.

[0018] Indoor unit 100 includes leak detection sensor 105 that detects a leak of the flammable refrigerant, leak detection sensor 105 being disposed in air blow circuit 108. According to the present exemplary embodiment, leak detection sensor 105 is provided near brazed portion 113 of indoor heat exchanger 101, specifically, provided below brazed portion 113 of indoor heat exchanger 101. Brazed portion 113 of indoor heat exchanger 101 is apt to be corroded or damaged. Disposing leak detection sensor 105 near brazed portion 113 of indoor heat exchanger 101 improves safety at the occurrence of a refrigerant leak.

[0019] Pipe connection housing section 107 is at the back of underframe 103. Underframe 103 includes partition 114 that partitions air blow circuit 108 off from pipe connection housing section 107. Pipe connector 102 connects the refrigerant pipe attached to indoor heat exchanger 101 to the refrigerant pipe attached to the outdoor heat exchanger. When indoor unit 100 is installed by a left-hand pipe connection method, pipe connection housing section 107 houses pipe connector 102 therein.

[0020] Indoor unit 100 includes communication path 110 provided between air blow circuit 108 and pipe connection housing section 107 to connect them to each other. When the refrigerant leaks in pipe connection housing section 107, the refrigerant is allowed to flow through communication path 110 to reach air blow circuit 108. Communication path 110 may be provided in partition 114 between air blow circuit 108 and pipe connection housing section 107. Communication path 110 may be formed in such a way as to penetrate machine chamber 106. It is preferable that an opening of communication path 110 that is closer to air blow circuit 108 be located near leak detection sensor 105.

[0021] Indoor unit 100 has pipe outlet hole 111 through which the refrigerant pipe emerges from indoor unit 100. It is preferable that the flow path area of communication path 110 be larger than the area of pipe outlet hole 111. In this configuration, the refrigerant leaking in pipe connection housing section 107 flows into air blow circuit 108 rather than flowing out of indoor unit 100, thus allowing leak detection sensor 105 provided in air blow circuit 108 to quickly detect the leaking refrigerant. This further improves safety at the occurrence of a refrigerant leak.

[0022] Outer panel 104 is formed into a shape slightly larger than underframe 103, and is installed in such a way as to cover underframe 103. In the present exemplary embodiment, underframe 103 and outer panel 104 are installed with almost no gap formed therebetween.

[0023] Operations and effects of the air conditioner configured in the above manner will hereinafter be described.

[0024] In the air conditioner of the present exemplary embodiment, the flammable refrigerant may leak from brazed portion 113 of indoor heat exchanger 101. Brazed portion 113 of indoor heat exchanger 101, when corroded or damaged, tends to cause a refrigerant leak. Because the flammable refrigerant has a specific gravity larger than that of air, the refrigerant, once it leaks out, flows downward from brazed portion 113 of indoor heat exchanger 101. The refrigerant flowing downward reaches leak detection sensor 105 provided near the brazed portion 113 of indoor heat exchanger 101, specifically, provided below brazing portion 113 of indoor heat exchanger 101, and consequently leak detection sensor 105 detects the leaking refrigerant.

[0025] As described above, pipe connector 102 of the present exemplary embodiment connects the refrigerant pipe attached to indoor heat exchanger 101 to the refrigerant pipe attached to the outdoor heat exchanger in the air conditioner. When the flammable refrigerant leaks from pipe connector 102, the leaking flammable refrigerant fills pipe connection housing section 107, thus flowing through communication path 110 to reach air blow circuit 108. The opening of communication path 110 that is closer to air blow circuit 108 is located near leak detection sensor 105. The flammable refrigerant having passed through communication path 110 reaches leak detection sensor 105. Hence, leak detection sensor 105 detects the leaking refrigerant.

[0026] In this manner, the air conditioner according to the present exemplary embodiment allows detection of the flammable refrigerant leaking from brazed portion 113 of indoor heat exchanger 101 and detection of the flammable refrigerant leaking from pipe connector 102 as well, and therefore can further improve safety at the time of occurrence of a refrigerant leakage. In addition, because one leak detection sensor 105 is able to detect refrigerant leaks of both cases, the manufacturing cost of the air conditioner can be reduced.

[0027] The air conditioner according to the present exemplary embodiment includes indoor heat exchanger 101 in indoor unit 100, the outdoor heat exchanger in the outdoor unit, pipe connector 102 connecting the refrigerant pipe attached to indoor heat exchanger 101 to the refrigerant pipe attached to outdoor heat exchanger, and the flammable refrigerant filling each of the refrigerant pipes. In the air conditioner, indoor unit 100 includes air blow circuit 108 housing indoor heat exchanger 101, pipe connection housing section 107 located on the back of the underframe 103 of indoor unit 100, pipe connection housing section 107 housing pipe connector 102, and leak detection sensor 105 that detects a leak of the flammable refrigerant, leak detection sensor 105 being disposed in air blow circuit 108, and indoor unit 100 further includes communication path 110 that communicatively connects fair blow circuit 108 to pipe connection housing section 107.

[0028] When indoor unit 100 is installed by a left-hand pipe connection method, pipe connector 102 is housed in pipe connection housing section 107. When the flammable refrigerant leaks from pipe connector 102, the flammable refrigerant flows through communication path 110 to reach leak detection sensor 105 in indoor unit 100. The air conditioner is thus able to detect the refrigerant leak and further improve safety at the occurrence of the refrigerant leak.

[0029] As stated in the description of the present exemplary embodiment, leak detection sensor 105 may be provided near brazed portion 113 of indoor heat exchanger 101.

[0030] Brazed portion 113 of indoor heat exchanger 101 is apt to be corroded or damaged. Disposing leak detection sensor 105 near brazed portion 113 of indoor heat exchanger 101 allows quick detection of a refrigerant leak, thus improving safety at the occurrence of a refrigerant leak.

[0031] In the present exemplary embodiment, indoor unit 100 includes pipe outlet hole 111 through which the refrigerant pipe connected to pipe connector 102 passes. The flow path area of communication path 110 may be larger than the area of pipe outlet hole 111.

[0032] This gives the flammable refrigerant leaking in pipe connection housing section 107 a tendency that the flammable refrigerant flows into air blow circuit 108 rather than flowing out of indoor unit 100. Leak detection sensor 105 provided in air blow circuit 108 is capable of quickly detecting a leak of the flammable refrigerant. This further improves safety at the occurrence of a refrigerant leakage.(Second exemplary embodiment)

[0033] An air conditioner according to a second exemplary embodiment of the present invention will be described. The second exemplary embodiment will be described, with focus placed on what is different from the first exemplary embodiment. In the second exemplary embodiment, constituent elements identical or equal with those of the first exemplary embodiment will be denoted by the same reference numerals. From the description of the second embodiment, a description overlapping the description of the first exemplary embodiment is omitted.

[0034] FIG. 2 is a schematic front view of an internal configuration of indoor unit 100 of the air conditioner according to a second exemplary embodiment. The second exemplary embodiment will hereinafter be described with reference to FIG. 2.

[0035] Indoor unit 100 includes partition 114 that partitions air blow circuit 108 off from pipe connection housing section 107, air blow circuit 108 and pipe connection housing section 107 being included in underframe 103 of indoor unit 100. An end surface of partition 114 that is closer to leak detection sensor 105 is at least partially opened. In the second exemplary embodiment, indoor unit 100 has gap 112 of 1 mm or more on at least a part of a space between partition 114 and outer surface panel 104, the gap serving as communication path 110. It is preferable that gap 112 be provided on the side closer to leak detection sensor 105 in indoor unit 100. In the present second exemplary embodiment, gap 112 is provided on the right side of indoor unit 100 in a front view thereof.

[0036] It is preferable that the flow path area of communication path 110, i.e., gap 112 be larger than the area of pipe outlet hole 111. This gives the flammable refrigerant leaking in pipe connection housing section 107 a tendency that the flammable refrigerant flows into air blow circuit 108 rather than flowing out of indoor unit 100. Leak detection sensor 105 provided in air blow circuit 108 is capable of quickly detecting a leak of the flammable refrigerant. This further improves safety at the occurrence of a refrigerant leakage.

[0037] Operations and effects of the air conditioner configured in the above manner will hereinafter be described.

[0038] Pipe connector 102 connects the refrigerant pipe attached to indoor heat exchanger 101 to the refrigerant pipe attached to the outdoor heat exchanger in the air conditioner. When the flammable refrigerant leaks from pipe connector 102 of the present exemplary embodiment, the leaking flammable refrigerant fills pipe connection housing section 107, flows through gap 112 between underframe 103 and outer panel 104 and through the end surface of partition 114 that is closer to leak detection sensor 105, and finally reaches leak detection sensor 105 in air blow circuit 108.

[0039] In this manner, the air conditioner according to the present exemplary embodiment allows detection of the flammable refrigerant leaking from brazed portion 113 of indoor heat exchanger 101 and detection of the flammable refrigerant leaking from pipe connector 102 as well, and therefore can further improve safety at the time of occurrence of a refrigerant leakage. In addition, because one leak detection sensor 105 is able to detect refrigerant leaks of both cases, the manufacturing cost of the air conditioner can be reduced.

[0040] The technology disclosed in the present specification can be applied also to equipment having a refrigerant pipe filled with a flammable refrigerant, such as an air conditioner and a refrigerator.

Claims

1. An air conditioner comprising: an indoor heat exchanger (101) in an indoor unit (100); an outdoor heat exchanger in an outdoor unit; a pipe connector (102) connecting a refrigerant pipe attached to the indoor heat exchanger (101) to a refrigerant pipe (109) attached to the outdoor heat exchanger; and a flammable refrigerant filling each of the refrigerant pipes, wherein the indoor unit (100) includes: an air blow circuit (108) housing the indoor heat exchanger (101); an underframe (103); a pipe connection housing section (107) located on a back surface of the underframe (103) of the indoor unit, the pipe connection housing section (107) housing the pipe connector (102); and a leak detection sensor (105) that detects a leak of the flammable refrigerant, the leak detection sensor (105) being disposed in the air blow circuit (108), and wherein the indoor unit (100) further includes a communication path (110) having a flow path area and communicatively connecting the air blow circuit (108) to the pipe connection housing section (107).

2. The air conditioner according to claim 1, wherein the leak detection sensor (105) is disposed near a brazed portion (113) of the indoor heat exchanger (101).

3. The air conditioner according to claim 1 or claim 2, wherein the underframe (103) includes a partition (114) that partitions the air blow circuit (108) off from the pipe connection housing section (107), and a gap (112) of 1 mm or more is provided in a space, or a part thereof, between the partition (114) and an outer panel (104) of the indoor unit (100), wherein the gap (112) defines one extension of the flow path area of the communication path (110).

4. The air conditioner according to any one of claim 1 to claim 3, wherein the indoor unit (100) has a pipe outlet hole (111) through which the refrigerant pipe (109) connected to the pipe connector (102) passes, and the flow path area of the communication path (110) is larger than an area of the pipe outlet hole (111).