JP6964533B2 - Air conditioning system - Google Patents

Description

The present invention relates to an air conditioning system capable of detecting leakage of refrigerant from a refrigerant pipe or a tube of a heat exchanger.

In recent years, it has been required to suppress the leakage of refrigerants such as chlorofluorocarbons, which promote global warming, into the atmosphere. Refrigerant leaks into the atmosphere when the refrigerant that was not recovered when disposing of equipment containing refrigerant such as an air conditioner leaks into the atmosphere, and when the refrigerant is leaked from the equipment or piping while the air conditioner is in use. May leak into the atmosphere.

Recent studies have shown that the amount of refrigerant that leaks into the atmosphere during equipment use is as much as the amount of refrigerant that leaks into the atmosphere when the equipment is disposed of. Therefore, it is required to detect the leakage of the refrigerant during the use of the device. It is also required to identify the location of the leak in order to carry out repairs to stop the refrigerant leak.

For this reason, sensors that sandwich a special substance whose capacitance changes when the refrigerating machine oil that leaks from the refrigerant pipe together with the refrigerant is adsorbed are attached to various parts of the refrigerant pipe from both sides to detect the refrigerant leakage and the location where the leakage occurs. A refrigerant leak detection device for specifying is proposed (see, for example, Patent Document 1).

JP-A-2010-101515

By the way, in order to identify the location where the refrigerant leaks to the extent that repairs can be performed to stop the refrigerant leak, it is necessary to attach sensors to many places in the refrigerant pipe. However, the conventional sensor described in Patent Document 1 has a complicated structure, and there is a problem that the air conditioning system becomes complicated when many sensors are attached to the refrigerant pipe.

Therefore, an object of the present invention is to provide an air conditioning system capable of detecting a leakage of a refrigerant and identifying a leaking portion with a simple configuration.

The air conditioning system of the present invention is a metal refrigerant pipe through which a refrigerant flows and a flexible insulating sheet having a metal thin film formed on the surface thereof. An air conditioning system including an electrode sheet assembly constituting a band and a capacitance meter for detecting a capacitance between the electrode band and the refrigerant pipe, wherein the refrigerant pipe does not reverse its inclination direction. The electrode sheet assembly includes a plurality of piping blocks, and is characterized in that the electrode sheet assembly is wound around a lower end portion of the piping block in the direction of gravity. Further, in the air conditioning system of the present invention, the air conditioning system includes a detection unit that detects a leakage point of the refrigerant based on the capacitance detected by the capacitance meter, and the detection unit includes a static electricity detected by the capacitance meter. The leaked piping block in which the refrigerant leaks may be specified from the plurality of piping blocks based on the electric capacity.

Since the refrigerant pipe is composed of a plurality of piping blocks whose inclination directions are not reversed, when a refrigerant leaks, the leaked refrigerant flows along the inclination toward the lower end of the piping block in the direction of gravity. .. Therefore, by wrapping the electrode sheet assembly around the lower end of the piping block in the direction of gravity, the leakage of the piping block can be detected, and the leakage location can be specified for each piping block. As a result, it is possible to detect the leakage of the refrigerant in the air conditioning system and identify the leakage location with a small number of electrode sheet assemblies. Further, by winding the electrode sheet assembly, which is a flexible insulating sheet having a metal thin film formed on the surface, around the refrigerant pipe, a substantially annular electrode band can be easily formed on the outer surface of the refrigerant pipe.

In the air conditioning system of the present invention, in the electrode sheet assembly, a plurality of the metal thin films are formed on the surface thereof, and when the electrode sheet assembly is wound around the outer periphery of the refrigerant pipe, the plurality of the metal thin films are substantially aligned in the longitudinal direction of the refrigerant pipe. A plurality of annular electrode bands are formed, the capacitance meter detects each capacitance between the plurality of electrode bands and the refrigerant pipe, and the detection unit is of one of the piping blocks. The capacitance between the electrode band on the upper side in the gravity direction and the refrigerant pipe is larger than the range of the capacitance variation between the electrode band and the refrigerant pipe on the lower side in the gravity direction of the pipe block. When it is large, one said pipe block may be specified as a leaked pipe block in which the refrigerant leaks.

Even if there are variations in the electrostatic capacity between the electrode band and the refrigerant pipe and it is difficult to identify the leak location due to changes in the electrostatic capacity, the electrostatic capacity between the electrode band on the upper side in the gravity direction of one piping block and the refrigerant pipe When the capacitance is larger than the range of the capacitance variation between the electrode band on the lower side in the direction of gravity and the refrigerant pipe, the piping block is identified as the leaking piping block in which the refrigerant leaks, so that the electrode band and the refrigerant Even when there is a variation in the electrostatic capacity between the pipe and the pipe, the leakage point of the refrigerant can be identified.

In the air conditioning system of the present invention, the piping block includes vertical piping, and the electrode sheet assembly may be wound around the lower end of the vertical piping in the direction of gravity.

Since the leaked refrigerant flows downward in the gravity direction along the vertical pipe, it is possible to detect the leakage of the refrigerant in each vertical pipe by arranging the electrode sheet assembly at the lower end in the gravity direction of the vertical pipe. can.

In the air conditioning system of the present invention, the air conditioning system includes a heat exchanger that constitutes a folded flow path arranged in multiple stages in the direction of gravity and includes a tube through which the refrigerant flows, and the electrode sheet assembly is a welded portion or a bent portion of the tube. It may be wrapped around the outer surface of the. Further, in the air conditioning system of the present invention, the electrode sheet assembly may be wound around the outer surface of the tube in the lower step in the direction of gravity.

Since the electrode sheet assembly is wound around a portion where a refrigerant leak is likely to occur, leakage can be effectively detected even with a small number of electrode sheet assemblies. Further, since the leaked refrigerant flows toward the lower stage tube, it is possible to detect the leakage of the refrigerant in the entire heat exchanger simply by arranging the electrode sheet assembly on the outer surface of the lower stage tube. ..

INDUSTRIAL APPLICABILITY The present invention can provide an air conditioning system capable of detecting a leakage of a refrigerant and identifying a leakage location with a simple configuration.

It is a system diagram which shows the structure of the air-conditioning system of an embodiment. It is a cross-sectional detailed perspective view of the part A shown in FIG. 1, and is the cross-sectional perspective view of the 1st floor piping block around which the electrode sheet assembly is wound. FIG. 2A is a plan view showing a state in which the electrode sheet assembly shown in FIG. 2 is unfolded in the circumferential direction, and is a perspective view showing a state in which the electrode sheet assembly is wound around an outer surface of a refrigerant pipe. It is explanatory drawing which shows the electrode sheet assembly attached to the tube of a heat exchanger.

Hereinafter, the air conditioning system 100 of the embodiment will be described with reference to the drawings. As shown in FIG. 1, the air-conditioning system 100 is a system for air-conditioning the interior of the building 30, and includes an outdoor unit 31 installed on the roof, an indoor unit 32 installed in the room on each floor, and an outdoor unit 31. It includes a metal refrigerant pipe 10 for connecting the indoor unit 32, an electrode sheet assembly 20 wound around the outer surface of the refrigerant pipe 10, a selector 26, a capacitance meter 25, and a detection unit 27. In the following description, the right side of the paper in FIG. 1 will be referred to as the east side, and the left side of the paper will be referred to as the west side.

As shown in FIG. 1, the refrigerant pipe 10 includes the vertical piping block V01, the first and second rooftop piping blocks R01 and R02 arranged on the roof and connecting the vertical piping block V01 and the outdoor unit 31, and the first floor. The first to third first floor piping blocks 101 to 103 arranged in the vertical piping block V01 and the indoor unit 32 on the first floor, and the vertical piping block V01 arranged on the second floor and the indoor unit 32 on the second floor are connected. It is composed of the first to third floor piping blocks 201 to 203 to be connected.

The first rooftop piping block R01 descends from west to east so that the height of the eastern end connected to the vertical piping block V01 is lower than the height of the western end connected to the second rooftop piping block R02. It is a piping block that inclines in the direction. That is, the first rooftop piping block R01 is a piping block that inclines downward from the west to the east and the inclination direction does not reverse. Therefore, the east side end connected to the vertical pipe block V01 is the lower end in the gravity direction of the first rooftop pipe block R01. The electrode sheet assembly 20 is wound around the eastern end.

Further, the second rooftop piping block R02 is east to west so that the height of the west end connected to the outdoor unit 31 is lower than the height of the eastern end connected to the first rooftop piping block R01. It is a piping block that inclines downward toward. That is, the second rooftop piping block R02 is a piping block that inclines downward from the east to the west and the inclination direction does not reverse. Therefore, the western end connected to the outdoor unit 31 is the lower end in the gravity direction of the second rooftop piping block R02. Then, the electrode sheet assembly 20 is wound around the western end.

Like the first rooftop piping block R01, the first and third floor piping blocks 101 and 103 and the first and third floor piping blocks 201 and 203 are inclined downward from the west to the east, and are inclined in the inclined direction. Is a piping block that does not reverse, and the electrode sheet assembly 20 is wound around the eastern end, which is the lower end in the direction of gravity. On the contrary, the 2nd floor piping block 102 and the 2nd floor piping block 202 are piping blocks that incline downward from east to west and do not reverse the inclination direction like the 2nd rooftop piping block R02. The electrode sheet assembly 20 is wound around the western end, which is the lower end in the direction.

The vertical piping block V01 is a piping block that extends in the vertical direction across a plurality of floors from the roof to the first floor along the wall of the building 30, and the electrode sheet assembly 20 is wound around the lower end, which is the lower end in the direction of gravity. Has been done.

As shown in FIG. 2, the electrode sheet assembly 20 is a flexible insulating sheet 21 having a metal thin film 22a formed on its surface, and is wound around the outer periphery of the refrigerant pipe 10 of the first floor piping block 101 to form a metal thin film. 22a constitutes a substantially annular electrode band 22. A heat insulating material 12 is attached to the outer periphery of the electrode sheet assembly 20, and the outer periphery of the heat insulating material 12 is covered with a cover 13.

As shown in FIG. 3A, the electrode sheet assembly 20 is formed by forming a plurality of metal thin films 22a on a flexible insulating sheet 21 such as a resin sheet, for example. The insulating sheet 21 is a rectangular sheet that is long in the longitudinal direction of the refrigerant pipe 10, and two metal thin films 22a are formed with a gap in the longitudinal direction of the refrigerant pipe 10. The circumferential length of the insulating sheet 21 is substantially the same as the outer peripheral length of the heat insulating material 12 covering the outer surface of the refrigerant pipe 10, and the metal thin film 22a extends in the circumferential direction of the insulating sheet 21. It is formed on 21. Further, each output terminal 23 of each metal thin film 22a is formed at an end portion of the insulating sheet 21 in the longitudinal direction, that is, an end portion in a direction perpendicular to the winding direction. Each output terminal 23 and each metal thin film 22a are connected by each wiring 24. Like the metal thin film 22a, each output terminal 23 is a metal thin film formed on the insulating sheet 21, and the wiring 24 is a linear metal thin film formed on the insulating sheet 21. The metal thin film 22a, the output terminal 23, and the wiring 24 form a conductive layer on the insulating sheet 21 by sputtering, vapor deposition, or the like, and remove parts other than the metal thin film 22a, the output terminal 23, and the wiring 24 by etching. The metal thin film 22a, the output terminal 23, and the wiring 24 may be printed on the insulating sheet 21 using the conductive ink.

As shown in FIG. 3B, when the electrode sheet assembly 20 shown in FIG. 3A was wound around the outer circumference of the metal refrigerant pipe 10, the flat metal thin film 22a was wound around the outer circumference of the refrigerant pipe 10. It becomes a substantially annular electrode band 22. The two electrode bands 22 are aligned with a gap in the longitudinal direction of the refrigerant pipe 10. Further, at the end of the refrigerant pipe 10 of the electrode sheet assembly 20 in the longitudinal direction, each output terminal 23 connected to each electrode band 22 is arranged.

ここで、
Ｌは、電極帯２２の冷媒管１０の長手方向の長さである。
ε_０は、真空の誘電率である。
ε_Ｓは、冷媒管１０の外面と電極帯２２との間の介在物（絶縁シート２１と空気）の統合比誘電率である。
Ｒ１は、冷媒管１０の外半径である。
Ｒ２は、絶縁シート２１の外半径である。 As shown in FIG. 2, when the electrode sheet assembly 20 is wound around the outer periphery of the refrigerant pipe 10, an annular shape having a predetermined capacitance C is formed between each electrode band 22 and the metal refrigerant pipe 10. A capacitor is formed. The capacitance C of the annular capacitor is calculated by the following equation (1).

here,
L is the length of the refrigerant pipe 10 of the electrode band 22 in the longitudinal direction.
ε ₀ is the permittivity of the vacuum.
ε _S is the integrated relative permittivity of inclusions (insulating sheet 21 and air) between the outer surface of the refrigerant pipe 10 and the electrode band 22.
R1 is the outer radius of the refrigerant pipe 10.
R2 is the outer radius of the insulating sheet 21.

As shown in FIG. 2, the two electrode bands 22 of the electrode sheet assembly 20 are connected to the selector 26 via the output terminals 23, respectively. The output end of the selector 26 is connected to the capacitance meter 25. Further, the refrigerant pipe 10 is also connected to the capacitance meter 25, and the capacitance meter 25 detects the capacitance C between each electrode band 22 and the refrigerant pipe 10. Further, the selector 26 and the capacitance meter 25 are connected to the detection unit 27. The detection unit 27 is a computer including a CPU and a memory inside, and operates a selector 26 to operate the selector 26 with each electrode band 22 of the electrode sheet assembly 20 of each piping block 101-103, 201-203, V01, R01, R02. The connection with the capacitance meter 25 is sequentially switched, the capacitance C detected by the capacitance meter 25 is acquired, and the leaked piping block in which the refrigerant 11 leaks is specified based on the capacitance C. ..

Hereinafter, a case where the liquid refrigerant 11 leaks in the first-floor piping block 101 shown in FIG. 1 will be described. When the liquid refrigerant 11 leaks from the refrigerant pipe 10 of the first floor piping block 101, the refrigerant 11 enters between the outer surface of the refrigerant pipe 10 and the heat insulating material 12. As described above, since the first floor piping block 101 is inclined downward from the west to the east, the leaked liquid refrigerant 11 is formed between the outer surface of the refrigerant pipe 10 and the heat insulating material 12. It moves toward the east side, which is the lower side in the direction of gravity. Then, the refrigerant 11 moves to the east side end, which is the lower end in the gravity direction of the first floor piping block 101, and enters between the electrode band 22 of the electrode sheet assembly 20 and the outer surface of the refrigerant pipe 10.

_{Since the relative permittivity of the liquid refrigerant 11 is larger than the integrated relative permittivity ε S of the} insulating sheet 21 and the air interposed between the electrode band 22 and the outer surface of the refrigerant pipe 10, the refrigerant 11 is the electrode band. When entering between 22 and the outer surface of the refrigerant pipe 10, _{the value of ε S} in the equation (1) becomes large. Therefore, the capacitance C between the electrode band 22 and the refrigerant pipe 10 is larger than the capacitance C in the non-leakage state. For example, when the specific attraction ratio of the liquid refrigerant 11 is 90, when leakage occurs, the capacitance C becomes a value about 10 times the capacitance C when there is no leakage.

Therefore, when the liquid refrigerant 11 leaks in the first-floor piping block 101, the detection unit 27 uses the selector 26 to set the electrode band 22 of the electrode sheet assembly 20 of the first-floor piping block 101 and the capacitance meter. When connected to 25, a large capacitance C about 10 times larger than usual is detected. Then, the detection unit 27 uses the first-floor piping block 101 as a leaking piping block in which the refrigerant 11 leaks when the capacitance C detected by the capacitance meter 25 exceeds the leakage determination threshold value. Identify. Then, the detection unit 27 displays the name of the leaky pipe block on a display (not shown) and issues an alarm.

At this time, the connection end of the second first floor piping block 102 with the first floor piping block 101 is at the highest position in the second first floor piping block 102. Therefore, even if the refrigerant 11 leaks from the second floor piping block 102 adjacent to the first floor piping block 101, the refrigerant 11 does not flow to the first floor piping block 101, and the refrigerant 11 does not flow to the first floor piping block 101. The capacitance C of the piping block 101 does not change. However, when the refrigerant 11 leaks in the vertical piping block V01 adjacent to the first floor piping block 101, the refrigerant 11 flows toward the lower end along the vertical piping block V01, so that the first floor piping block The capacitance C of 101 may change. In this case, the refrigerant 11 that has flowed toward the lower end along the vertical pipe block V01 first enters between the electrode band 22 of the electrode sheet assembly 20 wound around the lower end of the vertical pipe block V01 and the refrigerant pipe 10. do. Therefore, the capacitance C of the vertical piping block V01 first increases and exceeds the threshold value. After that, the refrigerant 11 enters the first-floor piping block 101 and is between the electrode band 22 of the electrode sheet assembly 20 and the refrigerant pipe 10 wound around the eastern end of the first-floor piping block 101. The capacitance C becomes large and exceeds the threshold value.

Therefore, when both the capacitance C of the first-floor piping block 101 and the capacitance C of the vertical piping block V01 adjacent to the first-floor piping block 101 exceed the threshold value, the detection unit 27 is the first. When the capacitance C of the first-floor piping block 101 exceeds the threshold value first, the first-floor piping block 101 is identified as the leaking piping block in which the refrigerant 11 has leaked. On the contrary, when the capacitance C of the vertical piping block V01 exceeds the threshold value first, the vertical piping block V01 is specified as the leaking piping block in which the refrigerant 11 has leaked. In this way, the detection unit 27 can identify the leaking piping block by determining the order in which the threshold values are exceeded even when the capacities of the adjacent piping blocks both exceed the threshold value.

Similarly, when a leak occurs in the second floor piping block 102 shown in FIG. 1, the refrigerant 11 flows toward the western end, which is the lower end in the direction of gravity, and the electrode sheet wound around this portion. The capacitance C between the electrode band 22 of the assembly 20 and the refrigerant pipe 10 increases. The leaked refrigerant 11 may flow from the second-floor piping block 102 to the eastern end, which is the lower end in the gravity direction of the adjacent third-floor piping block 103. In this case, after the capacitance C between the electrode band 22 of the electrode sheet assembly 20 and the refrigerant pipe 10 wound around the second first floor piping block 102 increases, the electrode sheet assembly 20 is wound around the second floor piping block 102. The capacitance C between the electrode band 22 of the electrode sheet assembly 20 and the refrigerant pipe 10 is increased. Therefore, the detection unit 27 uses the refrigerant when the capacitance C between the electrode band 22 of the electrode sheet assembly 20 wound around the second first floor piping block 102 and the refrigerant pipe 10 becomes large first. It can be identified that the leakage of 11 occurred in the second floor piping block 102. The detection unit 27 can identify the leaked pipe block in the same manner when a leak occurs in another pipe block.

As described above, when the refrigerant 11 leaks in each of the piping blocks 101-103, 201-203, V01, R01, and R02, the electrode band 22 of the electrode sheet assembly 20 wound around the leaked piping block. Since the capacitance C between the refrigerant pipe 10 and the refrigerant pipe 10 is increased first, it is possible to identify in which pipe block the leakage of the refrigerant 11 has occurred. As a result, the detection unit 27 can identify the leak location for each pipe block.

Further, the refrigerant 11 may leak from the refrigerant pipe 10 in a gaseous state with the refrigerating machine oil. The refrigerating machine oil moves downward in the direction of gravity along the gradient of each piping block like the liquid refrigerant 11, and enters between the electrode band 22 of the electrode sheet assembly 20 and the outer surface of the refrigerant pipe 10. When the relative permittivity of the refrigerating machine oil is about 5, when the refrigerating machine oil enters between the electrode band 22 and the outer surface of the refrigerant pipe 10, the capacitance C is about 5 times the capacitance C when there is no leakage. It becomes a value. As a result, the detection unit 27 can detect the leakage and identify the leakage location even when the refrigerant 11 leaks in a gaseous state.

The case where the refrigerant 11 leaks from the refrigerant pipe 10 has been described above. Next, with reference to FIG. 4, the leakage detection of the refrigerant 11 from the heat exchanger 40 installed inside the outdoor unit 31 and the indoor unit 32 has been described. Will be described. The same parts as those described above with reference to FIGS. 1 to 3 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 4, the heat exchanger 40 mounted inside the outdoor unit 31 and the indoor unit 32 has U-shaped return bends 42 at both ends of a straight tube 41 having fins 44 attached to the outer surface. It is formed by welding at the welded portion 43 to form a multi-stage folded flow path in the direction of gravity. The refrigerant 11 flows inside, and the atmosphere or indoor air flows outside the fins 44 to exchange heat with the atmosphere or indoor air.

In such a heat exchanger 40, leakage often occurs at the welded portion 43 or the return bend 42 which is the bent portion. Therefore, as shown in FIG. 4, the electrode sheet assembly 20 is wound around the welded portion 43 and the return bend 42. The electrode band 22 of each electrode sheet assembly 20 is connected to the capacitance meter 25 via the selector 26, and one end of the tube 41 is connected to the capacitance meter 25. As described in the previous embodiment, the detection unit 27 detects the change in capacitance C between the electrode band 22 and the tube 41 by the capacitance meter 25, thereby detecting the tube in the heat exchanger 40. It is possible to detect the leakage of the refrigerant from 41 and identify the leakage location.

Further, since the tubes 41 of the heat exchanger 40 are arranged in multiple stages in the direction of gravity, when the refrigerant 11 leaks from the tube 41, the refrigerant 11 is arranged on the lower side in the direction of gravity. It flows to the surface of 41. Therefore, as shown in the folded portion on the right side of FIG. 4, the leakage of the refrigerant 11 from the heat exchanger 40 can be detected by winding the electrode sheet assembly 20 around the outer surface of the tube 41 in the lower stage in the direction of gravity. can. In this case, leakage of the refrigerant 11 from the heat exchanger 40 can be detected with a small number of electrode sheet assemblies 20.

As described above, the air conditioning system 100 of the present embodiment can detect the leakage of the refrigerant 11 and identify the leakage location with a simple configuration.

Next, other operations in the air conditioning system 100 of the present embodiment will be described. The capacitance C between the electrode band 22 and the refrigerant pipe 10 may vary depending on environmental factors. Therefore, when a change in the capacitance C between the electrode band 22 and the refrigerant pipe 10 is detected, is it a change in the capacitance C due to an environmental factor or a change in the capacitance C due to leakage of the refrigerant 11. May be difficult to determine.

Therefore, in this operation, the capacitance CU of the electrode band 22 on the upper side in the gravity direction and the refrigerant pipe 10 of one piping block varies from the capacitance CD between the electrode band 22 on the lower side in the gravity direction and the refrigerant pipe 10. When it is larger than the range, the piping block is specified as a leaking piping block in which the refrigerant 11 has leaked.

Hereinafter, a case where the liquid refrigerant 11 leaks in the first-floor piping block 101 shown in FIG. 1 will be described. As described above, when the liquid refrigerant 11 leaks from the refrigerant pipe 10 of the first floor piping block 101, the refrigerant 11 enters between the outer surface of the refrigerant pipe 10 and the heat insulating material 12, and the refrigerant pipe 10 enters. It moves between the outer surface and the heat insulating material 12 toward the east side, which is the lower side in the direction of gravity. Then, the refrigerant 11 moves to the east side end, which is the lower end in the gravity direction of the first-floor piping block 101, and first of the two electrode bands 22 of the electrode sheet assembly 20, the upper electrode band in the gravity direction. It enters between 22 and the outer surface of the refrigerant pipe 10. As a result, the capacitance CU between the electrode band 22 on the upper side in the direction of gravity and the refrigerant pipe 10 becomes large. At this time, the refrigerant 11 has not yet flowed between the electrode band 22 on the lower side in the direction of gravity and the outer surface of the refrigerant pipe 10. Therefore, the capacitance CD of the electrode band 22 on the lower side in the direction of gravity and the refrigerant pipe 10 has a capacitance C of a normal size.

The detection unit 27 operates the selector 26 to obtain the capacitance CU of the electrode band 22 on the upper side in the gravity direction and the refrigerant pipe 10 and the electrode band 22 and the refrigerant pipe 10 on the lower side in the gravity direction by the capacitance meter 25. Acquires the capacitance CD of.

In this case, the capacitance CU of the electrode band 22 on the upper side in the gravity direction and the refrigerant pipe 10 adjacent to the electrode band 22 on the lower side in the gravity direction also fluctuates due to environmental factors like the capacitance CD. Therefore, in the detection unit 27, when the capacitance CU of the electrode band 22 on the upper side in the gravity direction and the refrigerant pipe 10 acquired by the capacitance meter 25 is larger than the range of the variation of the capacitance CD. In addition, the change in capacitance CU exceeds the change due to environmental factors, and it is determined that it is due to the leakage of the refrigerant 11, and the first floor piping block 101 is referred to as the leaking piping block in which the leakage of the refrigerant 11 has occurred. Identify. Then, the detection unit 27 displays the name of the piping block in which the leak has occurred on a display (not shown) and issues an alarm.

Similarly, in the other piping blocks 102-103, 201-203, V01, R01, and R02, the detection unit 27 has the capacitance of the electrode band 22 on the upper side in the gravity direction and the refrigerant pipe 10 acquired by the capacitance meter 25. When the CU is large beyond the range of variation of the capacitance CD, the piping block is identified as a leaking piping block.

As described in the previous operation, for example, the capacitance C of the first floor piping block 101 may change due to leakage in the vertical piping block V01. In this case, the refrigerant 11 enters between the electrode band 22 on the lower side in the gravity direction of the first piping block 101 and the refrigerant pipe 10, and the capacitance CD on the lower side in the gravity direction increases. At this time, the refrigerant 11 does not enter between the electrode band 22 on the upper side in the gravity direction and the refrigerant pipe 10, and the capacitance CU on the upper side in the gravity direction remains at a normal value. Therefore, the capacitance CU is smaller than the capacitance CD, and the capacitance CU does not increase beyond the range of variation of the capacitance CD. Therefore, in this case, the detection unit 27 does not specify the first floor piping block 101 as the leaking piping block. As described above, in this operation, even when the refrigerant 11 leaks in the adjacent piping block, it is possible to prevent the piping block in which the leakage does not occur from being erroneously identified as the leaking piping block.

As described above, according to this operation, even if there is a variation in the capacitance C between the electrode band 22 and the refrigerant pipe 10 and it is difficult to identify the leaked portion due to the change in the capacitance C, the refrigerant 11 The leak location can be identified. Further, even when the refrigerant 11 leaks in the adjacent piping block, it is possible to prevent the piping block in which the leakage has not occurred from being erroneously identified as the leaking piping block.

10 Refrigerant pipe, 11 Refrigerant, 12 Insulation material, 13 Cover, 20 Electrode sheet assembly, 21 Insulation sheet, 22 Electrode band, 22a metal thin film, 23 Output terminal, 24 Wiring, 25 Capacitometer, 26 Selector, 27 Detector , 30 buildings, 31 outdoor units, 32 indoor units, 40 heat exchangers, 41 tubes, 42 return bends, 43 welds, 44 fins, 100 air conditioning systems, 101-103 first floor piping blocks, 201-203 second floor piping blocks, R01, R02 Roof piping block, V01 Vertical piping block.

Claims (6)

A metal refrigerant pipe through which the refrigerant flows and
A flexible insulating sheet having a metal thin film formed on its surface, and an electrode sheet assembly that is wound around the outer periphery of the refrigerant pipe to form a substantially annular electrode band.
An air conditioning system including a capacitance meter that detects the capacitance between the electrode band and the refrigerant pipe.
The refrigerant pipe includes a plurality of piping blocks whose inclination directions are not reversed.
The electrode sheet assembly is wound around the lower end of the piping block in the direction of gravity.
An air conditioning system featuring. The air conditioning system according to claim 1.
A detection unit that detects a leakage point of the refrigerant based on the capacitance detected by the capacitance meter is included.
The detection unit identifies the leaking pipe block in which the refrigerant leaks from the plurality of pipe blocks based on the capacitance detected by the capacitance meter.
An air conditioning system featuring. The air conditioning system according to claim 2.
In the electrode sheet assembly, a plurality of the metal thin films are formed on the surface thereof, and when the metal thin films are wound around the outer periphery of the refrigerant pipe, the plurality of the metal thin films are aligned in the longitudinal direction of the refrigerant pipe. Configure and
The capacitance meter detects each capacitance between the plurality of electrode bands and the refrigerant pipe, and detects each capacitance.
The detection unit includes the electrode band and the refrigerant pipe on the lower side in the gravity direction of the piping block having a capacitance between the electrode band on the upper side in the gravity direction of the piping block and the refrigerant pipe. Identifying one of the piping blocks as a leaking piping block in which the refrigerant has leaked when it is larger than the range of the capacitance variation between the two.
An air conditioning system featuring. The air conditioning system according to any one of claims 1 to 3.
The piping block includes vertical piping.
The electrode sheet assembly is wound around the lower end of the vertical pipe in the direction of gravity.
An air conditioning system featuring. The air conditioning system according to any one of claims 1 to 4.
It includes a heat exchanger that constitutes a folded flow path arranged in multiple stages in the direction of gravity and has a tube through which the refrigerant flows.
The electrode sheet assembly is wound around the outer surface of the welded or bent portion of the tube.
An air conditioning system featuring. The air conditioning system according to claim 5.
The electrode sheet assembly is wound around the outer surface of the tube in the lower step in the direction of gravity.
An air conditioning system featuring.

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