Heat medium circulation device
Patent Information
- Application Number
- EP2022898203
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2021-11-29
- Filing Date
- 2022-09-09
- Publication Date
- 2025-03-26
AI Technical Summary
Existing heat medium circulation devices using flammable refrigerants face safety concerns due to the risk of ignition when refrigerant leaks into the electrical box, which can act as an ignition source.
The device is designed with a heat source-side circuit and a use-side circuit, where the flammable refrigerant and heat medium flow through an intermediate heat exchanger, and a gas discharge device, such as an air vent valve or pressure relief valve, is housed in a separate space isolated from the electrical box by partition walls, reducing the likelihood of refrigerant contact with electrical components.
This configuration significantly lowers the probability of refrigerant reaching the electrical box's power terminal and components, thereby reducing the ignition risk and enhancing safety by isolating the flammable refrigerant from potential ignition sources.
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Abstract
Description
[TECHNICAL FIELD]
[0001] The present invention relates to a heat medium circulation device comprising a heat source-side circuit and a use-side circuit.[BACKGROUND TECHNIQUE]
[0002] Patent Document 1 discloses a heat pump device comprising a heat source-side circuit using flammable refrigerant, and a use-side circuit. This heat pump device houses the heat source-side circuit, a heat medium heat exchanger, and the use-side circuit in an outdoor unit, and a refrigerant discharge valve composed of at least one of a pressure relief valve and an air vent valve is provided in the use-side circuit.
[0003] And the outdoor unit is provided with a first space provided with at least a compressor of the heat source-side circuit, and the refrigerant discharge valve is provided in a second space partitioned from the first space.[PRIOR ART DOCUMENT][PATENT DOCUMENT][Patent Document 1] EP3312531B1(WO2018 / 047265A1)[SUMMARY OF THE INVENTION][PROBLEM TO BE SOLVED BY THE INVENTION]
[0004] The present invention provides a heat medium circulation device excellent in safety by assuming in the event that flammable refrigerant is leaked in an outdoor unit composed of a heat source-side circuit using flammable refrigerant, a refrigerant / heat medium heat exchanger, and an air vent valve and a pressure relief valve that are part of the use-side circuit, ensuring that an electrical box does not become an ignition source even in such cases.[MEANS FOR SOLVING THE PROBLEM]
[0005] A heat medium circulation device according to the present invention comprises a heat source-side circuit in which a compressor, an intermediate heat exchanger, an expansion device, and a heat source-side heat exchanger are sequentially connected in an annular shape through a refrigerant pipe, and an outdoor blower for blowing air to the heat source-side heat exchanger, and a use-side circuit in which a conveyance pump for conveying heat medium, the intermediate heat exchanger, and a use-side heat exchanger is sequentially connected in an annular shape through a heat medium pipe, and an electrical box composed of a control board for controlling operation of the compressor, the expansion device, and the outdoor blower, and power supply parts, wherein the heat source-side circuit is charged with flammable refrigerant, the use-side circuit is charged with the heat medium, the flammable refrigerant and the heat medium flow in the intermediate heat exchanger, the heat medium pipe has a gas discharge device consisting of at least an air vent valve or a pressure relief valve, the gas discharge device is housed in a space C, and the space C and the electrical box are isolated by at least one or more partition walls.[EFFECT OF THE INVENTION]
[0006] In a heat medium circulation device according to the present invention, even if flammable refrigerant, which is charged into a heat source-side circuit, is discharged from a gas discharge device due to leak from an intermediate heat exchanger or due to mix into a use-side circuit through the intermediate heat exchanger, a probability that the refrigerant reaches contact of a power terminal and an electronic component in an electrical box which can be an ignition source is extremely low. As a result, an ignition risk in the electrical box can be eliminated and safety can be further improved.[BRIEF DESCRIPTION OF THE DRAWINGS]
[0007] Fig. 1 is a schematic configuration diagram of a heat medium circulation device in a first embodiment in the present invention; Fig. 2 is a schematic configuration diagram of a heat medium circulation device in a second embodiment in the present invention; and Fig. 3 is a schematic configuration diagram of a heat medium circulation device in a third embodiment in the present invention. [MODE FOR CARRYING OUT THE INVENTION](Perception which becomes a basis of the present invention)
[0008] In general, a heat medium circulation device includes, within a use-side circuit, an air vent valve for air bleeding during equipment installation, and a pressure relief valve serving as a safety device in an event that pressure of heat medium exceeds a predetermined pressure. Therefore, when flammable refrigerant flows into the use-side circuit, the flammable refrigerant is discharged outside the circuit through the air vent valve or the pressure relief valve.
[0009] Therefore, in the industry, enhancing the safety of heat medium circulation device that use flammable refrigerant is a problem. Consequently, a common product design for an outdoor unit, which consist of a heat source-side circuit, a refrigerant / heat medium heat exchanger, and parts of a use-side circuit such as an air vent valve and a pressure relief valve, aimed to enhance explosion-proof properties of each electronic component with high risk of ignition, thereby reducing a probability of ignition even in presence of flammable refrigerant.
[0010] Under such circumstances, in order to improve safety, taking as a hint that an ignition probability of flammable refrigerant can be expressed as product of three factors (a refrigerant leakage probability, an ignition source existence probability, and an encounter probability between flammable refrigerant and ignition source), the inventors thought that it was necessary to reduce the ignition probability of flammable refrigerant. As one measure to achieve this, an idea was obtained that it can be handled by reducing the encounter probability between flammable refrigerant and ignition source of the above elements.
[0011] Then, the inventors found that in order to realize the idea, there is a problem that it is necessary to pursue multiple safety design so that the flammable refrigerant and the ignition source do not encounter as much as possible. In order to solve the problem, the subject matter of the present invention has been constructed.
[0012] Therefore, the present invention provides a heat medium circulation device comprises a heat source-side circuit in which a compressor, an intermediate heat exchanger, an expansion device, and a heat source-side heat exchanger are sequentially connected in an annular shape through a refrigerant pipe, and an outdoor blower for blowing air to the heat source-side heat exchanger, and a use-side circuit in which a conveyance pump for conveying heat medium, the intermediate heat exchanger, and a use-side heat exchanger is sequentially connected in an annular shape through a heat medium pipe, and an electrical box composed of a control board for controlling operation of the compressor, the expansion device, and the outdoor blower, and power supply parts, wherein the heat source-side circuit is charged with flammable refrigerant, the use-side circuit is charged with the heat medium, the flammable refrigerant and the heat medium flow in the intermediate heat exchanger, the heat medium pipe has a gas discharge device consisting of at least an air vent valve or a pressure relief valve, the gas discharge device is housed in a space C, and the space C and the electrical box are isolated by at least one or more partition walls.
[0013] Hereinafter, embodiments will be described in detail with reference to the drawings. However, more detailed explanations may be omitted than necessary. For example, a detailed description of an already well-known matter or a duplicate description for substantially the same configuration may be omitted.
[0014] The accompanying drawings and the following description are provided for a person skilled in the art to sufficiently understand the present invention, and are not intended that they limit the subject matter described in claims.(First Embodiment)[1-1. Configuration]
[0015] Fig. 1 is a schematic configuration diagram of a heat medium circulation device according to a first embodiment of the present invention. In Fig. 1, a heat medium circulation device 10 is configured by an outdoor unit 11 and an indoor unit 12.
[0016] In a heat source-side circuit 20, a compressor 22, an intermediate heat exchanger (a refrigerant / heat medium heat exchanger) 23, an expansion device 24, and a heat source-side heat exchanger 25 are sequentially connected in an annular shape through a refrigerant pipe 21. An outdoor blower 26 blows air to the heat source-side heat exchanger 25. Flammable refrigerant is charged in the heat source-side circuit 20.
[0017] In a use-side circuit 30, a conveyance pump 32 for conveying heat medium, the intermediate heat exchanger 23, and a use-side heat exchanger 33 are sequentially connected in an annular shape through a heat medium pipe 31. Heat medium is charged in the use-side circuit 30. The flammable refrigerant and the heat medium flow through the intermediate heat exchanger 23.
[0018] Refrigerant absorbs heat from the outside air in the heat source-side heat exchanger 25, is compressed to high temperature and high pressure in the compressor 22, and radiates heat in the intermediate heat exchanger 23. The heat medium is heated by exchanging heat with the flammable refrigerant in the intermediate heat exchanger 23, and circulates through the use-side circuit 30 by the conveyance pump 32, thereby dissipating heat in the use-side heat exchanger 33. Further, a terminal device 41 is connected to the indoor unit 12, and the terminal device 41 is used for hot water heating and hot water supply. Water or antifreeze solution is used as the heat medium.
[0019] In the outdoor unit 11, the compressor 22, the intermediate heat exchanger 23, the expansion device 24, the heat source-side heat exchanger 25, the outdoor blower 26, and an electrical box 27 are installed.
[0020] The conveyance pump 32 and the use-side heat exchanger 33 are installed in the indoor unit 12.
[0021] The outdoor unit 11 and the indoor unit 12 are connected through the heat medium pipe 31.
[0022] The electrical box 27 composed of a control board for controlling operation of the compressor 22, the expansion device 24, and the outdoor blower 26, and power supply parts.
[0023] The heat medium pipe 31 has a gas discharge device 50 including at least an air vent valve 51 or a pressure relief valve 52. The air vent valve 51 discharges gas phase component contained in the use-side circuit 30. The pressure relief valve 52 is operated when the pressure of the use-side circuit 30 is excessively increased.
[0024] The outdoor unit 11 forms a space A, a space B, and a space C.
[0025] In the space A, the compressor 22 and the expansion device 24 are installed. In the space B, the heat source-side heat exchanger 25, the outdoor blower 26 and the electrical box 27 are installed. In the space C, the use-side heat exchanger 33 and the gas discharge device 50 are installed.
[0026] The electrical box 27 is covered with a housing 27a, and the housing 27a functions as a first partition wall.
[0027] The space A in which the compressor 22 is installed and the space B in which the electrical box 27 is arranged are separated and isolated by a soundproof plate 28, and the soundproof plate 28 functions as a second partition wall.
[0028] The space A and the space C are isolated by a partition wall 29, and the partition wall 29 functions as a third partition wall.
[0029] As described above, the electrical box 27 and the space C are isolated by the first partition wall 27a, the second partition wall 28, and the third partition wall 29. The intermediate heat exchanger 23 and the gas discharge device 50 are housed in the space C, and the space C and the electrical box 27 are isolated by at least one or more partition walls. In this way, even if the flammable refrigerant charged into the heat source-side circuit 20 leaks from the intermediate heat exchanger 23 or is mixed in the use-side circuit 30 through the intermediate heat exchanger 23 and is discharged from the gas discharge device 50, a probability that the refrigerant reaches contact of a power terminal and an electronic component in the electrical box 27 which can be an ignition source is extremely low. As a result, an ignition risk in the electrical box 27 can be reduced, and safety can be further improved.
[0030] The electrical box 27 is installed at the top of the space B, and the space C is installed at the bottom of the space A. In this way, it is preferable that the electrical box 27 is arranged above in the space B and the space C is arranged below in the space A.
[0031] The indoor unit 12 is installed in the air-conditioned space and is composed of a conveyance pump 32 that conveys the heat medium and a use-side heat exchanger 33 that exchanges heat with the heat medium.
[0032] The outdoor unit 11 is physically isolated into three spaces A, B and C by the partition walls 27a, 28, and 29, respectively.
[0033] The space A in which the compressor 22 is housed, and the space B in which the electrical box 27, the heat source-side heat exchanger 25, and the outdoor blower 26 are housed are isolated by the soundproof plate 28. Further, the electrical box 27 is installed above in the space B.
[0034] The pressure relief valve 52 has a communication pipe 62a that discharges gas. The communication pipe 62a discharges gas outside the outdoor unit 11 without passing through the space A and the space B.[1-2. Action]
[0035] The operation and action of the heat medium circulation device 10 configured as described above will be described below.
[0036] The operation of the heat medium circulation device 10 will be described based on Fig. 1.
[0037] Even if the flammable refrigerant leaks in the heat source-side circuit 20 of the heat medium circulation device 10, the probability that refrigerant reaches the contact of the power terminal and the electronic component installed in the housing 27a of the electrical box 27 which can be an ignition source. A probability of refrigerant reaching is low.
[0038] A plurality of heat transfer partition walls (not shown) are provided between the refrigerant and the heat medium in the refrigerant / heat medium heat exchanger 23. If a part of the plurality of heat transfer partition walls is damaged for some reason, there is a risk that the refrigerant of the high-pressure heat source-side circuit 20 flows into the low-pressure use-side circuit 30. Further, when a heat medium side flow path in the refrigerant / heat medium heat exchanger 23 is frozen and expanded to generate cracks, there is a risk that the refrigerant leaks to the space C side of the refrigerant / heat medium heat exchanger 23.
[0039] Even in such cases, the air vent valve 51, the pressure relief valve 52, and the refrigerant / heat medium heat exchanger 23 in the use-side circuit 30 in the space C are isolated from the space A by the partition wall 29, and the space A and the space B are further isolated by the soundproof plate 28. Therefore, the flammable refrigerant flows into the use-side circuit 30 and is discharged from the air vent valve 51 and the pressure relief valve 52. Alternatively, even if the flammable refrigerant leaks from the refrigerant / heat medium heat exchanger 23, the high-risk electrical box 27 serving as an ignition source is located in the space B, and the power terminal and the electronic component inside the housing 27a of the electrical box 27 are isolated from the space C by triple partition walls 27a, 28 and 29 of the housing 27a of the electrical box 27, the partition wall 29 of space C, and the soundproof plate 28. Therefore, the probability that the flammable refrigerant diffused in the space C reaches the electrical box 27 through the triple partition walls 27a, 28 and 29 is significantly reduced.
[0040] Further, when the flammable refrigerant used in the heat source-side circuit 20 of the heat medium circulation device 10 has a specific gravity higher than that of air, the space C is installed at the lowest part in the space A, and the electrical box 27 is installed at the top in the space B. Therefore, the probability that the refrigerant heavier than the air diffused into the space C reaches the electrical box 27, which is located above, is further reduced.[1-3. Effect and the like]
[0041] As described above, in the present embodiment, the electrical box 27 is installed at the top in the space B isolated from the space A in which the compressor 22 is stored. The space C surrounded by the partition wall 29 is installed at the lowest part in the space A, and houses the air vent valve 51, the pressure relief valve 52, and the refrigerant / heat medium heat exchanger 23 in the space C.
[0042] As a result, even if leakage of the flammable refrigerant occurs in the heat source-side circuit 20, the probability that the refrigerant reaches the contact of the power terminal and the electronic component in the housing 27a of the electrical box 27 which can be the ignition source is reduced in the use-side circuit 30.
[0043] Furthermore, even if the flammable refrigerant is discharged from the air vent valve 51, the pressure relief valve 52 and the refrigerant / heat medium heat exchanger 23, the probability that the flammable refrigerant heavier than air reaches, from the space C through gaps in the triple partition walls 27a, 28, and 29, the contact of the power terminal and the electronic component in the housing 27a of the electrical box 27, which is installed at the highest place in the space B (an ignition source encounter probability), is significantly reduced. Additionally, through the gaps in a single partition wall, the probability that the flammable refrigerant reaches, from the space C through a gap in a single partition wall, the power section of the compressor 22 or refrigerant components in the space A, and reaches a lower flammability limit concentration (LFL) (an ignition source encounter probability) is also significantly reduced.
[0044] Therefore, regardless of whether the device is operating or not, by reducing the ignition risk at the electrical box 27, as well as at the compressor 22 and refrigerant components, it is possible to provide a heat medium circulation device 10 with further improved safety.(Second Embodiment)[2-1. Configuration]
[0045] Fig. 2 shows a schematic configuration diagram of a heat medium circulation device according to a second embodiment of the present invention. In Fig. 2, the basic configuration is the same as in the first embodiment. That is, a heat medium circulation device 10 is composed of an outdoor unit 11 and an indoor unit 12, the outdoor unit 11 is physically isolated into three spaces A, B and C, by the partition walls 27a, 28 and 29, respectively.
[0046] In the second embodiment of the present invention, vents 61a, 61b are provided. The vents 61a, 61b introduce air from outside of the outdoor unit 11 into the space C and discharge the air in the space C to the outside of the outdoor unit 11.
[0047] The first vent 61a for introducing outside air and ventilating above in the space C in Fig. 2 and the second vent 61b for introducing outside air and ventilating below in the space C in Fig. 2 are provided.
[0048] The vents 61a, 61b do not communicate the space C and the space A, and do not communicate the space C and the space B.[2-2. Action]
[0049] The operation and action of the heat medium circulation device 10 configured as described above will be described.
[0050] In the event that the flammable refrigerant is discharged from the air vent valve 51, the pressure relief valve 52, and the refrigerant / heat medium heat exchanger 23 in the space C, the outside air flows in from the first vent 61a and the second vent 61b, and the air and the leaked refrigerant are mixed in the space C.
[0051] The two vents 61a, 61b are present. Therefore, an airflow in which outside air flows in through one of the vents and an airflow in which mixed gas of air in the space C and a leaked refrigerant flows out of the outdoor unit 11 through the other vent is generated.[2-3. Effect and the like]
[0052] As described above, in the present embodiment, the first vent 61a for introducing outside air and ventilating located above in the space C and a second vent 61b for introducing outside air and ventilating located below in the space C are provided.
[0053] As a result, in the event that the flammable refrigerant is discharged from the air vent valve 51, the pressure relief valve 52, and the refrigerant / heat medium heat exchanger 23 in the space C, outside air flows in from either the first vent 61a or the second vent 61b, and the leaked refrigerant mixed with the air in the space C is discharged from the other to the outside of the outdoor unit 11.
[0054] Therefore, the amount of flammable refrigerant staying in the space C decreases, the refrigerant concentration in space C decreases, and the probability that the concentration of the refrigerant reaches the power supply portion of the compressor 22 in the space A or the contact of the power terminal and the electronic component in the electrical box 27 in the space C reaches the lower flammability limit concentration (LFL) is significantly reduced. Therefore, an ignition risk in the electrical box 27 can be further reduced.
[0055] Furthermore, even if the space C which houses the air vent valve 51, the pressure relief valve 52 and the refrigerant / heat medium heat exchanger 23 is isolated by the partition wall from the space A, where the compressor 22 whose operating noise becomes noise pollution is housed. Therefore, the operating noise of the compressor 22 does not propagate from the first vent 61a or the second vent 61b of the space C to the outside of the outdoor unit 11.
[0056] Therefore, even if refrigerant leaks into a use-side circuit 30 and the flammable refrigerant diffuses into the space C, an ignition probability in the electrical box 27 can be reduced without propagating the operating noise of the compressor 22 to outside of the machine. Therefore, it is possible to achieve both safety and quietness.(Third Embodiment)
[0057] Fig. 3 shows a schematic configuration diagram of the heat medium circulation device according to a third embodiment of the present invention. In Fig. 3, the basic configuration is the same as in the first embodiment. That is, a heat medium circulation device 10 is composed of an outdoor unit 11 and an indoor unit 12, and the outdoor unit is physically isolated into three spaces A, B and C by partition walls 27a, 28 and 29, respectively.
[0058] In the space C in Fig. 3, a communication pipe 62b that communicates the outside air to an exhaust port of an air vent valve 51 is provided. In this way, the gas discharge device 50 has communication pipes 62a, 62b that discharge gas, and the communication pipes 62a, 62b discharge gas to the outside of the outdoor unit 11 without passing through the space A and the space B.[3-2. Action]
[0059] The operation and action of the heat medium circulation device 10 configured as described above will be described.
[0060] When the flammable refrigerant is discharged from the air vent valve 51 in the space C, the refrigerant is not discharged into the space C and is discharged directly to the outside of the outdoor unit 11 through the communication pipe 62b.[3-3. Effect and the like]
[0061] As described above, in the present embodiment, the communication pipe 62b that communicates the outside air to the exhaust port of the air vent valve 51 in the space C is provided.
[0062] As a result, even if the flammable refrigerant is discharged from the air vent valve 51 in the space C, the refrigerant is not discharged into the space C, and is discharged directly to the outside of the outdoor unit 11 through the communication pipe 62b.
[0063] Therefore, the flammable refrigerant does not stay in the space C, the refrigerant discharged from the use-side circuit 30 does not reach the power supply portion of the compressor 22 in the space A, nor the contact of the power terminal and the electronic component in the electrical box 27 in the space C.
[0064] As a result, even if the flammable refrigerant is discharged through the air vent valve 51 in the space C, the power supply portion of the compressor 22 and the contact of the power terminal and the electronic component in the electrical box 27 do not become ignition sources. Therefore, it is possible to provide the heat medium circulation device 10 having further improved safety.
[0065] Since the above-described embodiments are intended to illustrate the technology in the present invention, various modifications, replacements, additions, omissions, etc. can be made within the scope of the claims or equivalent thereto.[INDUSTRIAL APPLICABILITY]
[0066] In the present invention, even if leakage of flammable refrigerant occurs in a heat source-side circuit, in a heat medium circulation device, a probability that the refrigerant reaches contacts of a power terminal and an electronic component in an electrical box that can be an ignition source in a heat medium circulation device is reduced. Furthermore, the flammable refrigerant leaks from the heat source-side circuit to a use-side circuit through an intermediate heat exchanger, and the flammable refrigerant is discharged from the air vent valve, a pressure relief valve, and the intermediate heat exchanger, the probability that the refrigerant reaches to the contacts of the power terminal and the electronic component in the electrical box that can be an ignition source is further reduced.
[0067] Therefore, it is possible to provide a device in which the ignition risk in the electrical box can be reduced in the heat medium circulation device using the flammable refrigerant and in which the safety can be further improved. Consequently, a heating device that heats heat mediums such as water or antifreeze solution and uses the generated hot water or hot air, and a device for cooling and freezing heat mediums such as water or antifreeze solution, that is, the present invention is applicable to a device for performing freezing, refrigeration, air conditioning, hot water supply, and the like.[DESCRIPTION OF SYMBOLS]
[0068] 10heat medium circulation device 11outdoor unit 12indoor unit 20heat source-side circuit 21refrigerant pipe 22compressor 23intermediate heat exchanger (refrigerant / heat medium heat exchanger) 24expansion device 25heat source-side heat exchanger 26outdoor blower 27electrical box 27ahousing (first partition wall) 28soundproof plate (second partition wall) 29partition wall (third partition wall) 30use-side circuit 31heat medium pipe 32conveyance pump 33use-side heat exchanger 41terminal device 50gas discharge device 51air vent valve 52pressure relief valve 61afirst vent 61bsecond vent 62a, 62bcommunication pipe A, B, Cspace
Claims
1. A heat medium circulation device comprising: a heat source-side circuit in which a compressor, an intermediate heat exchanger, an expansion device, and a heat source-side heat exchanger are sequentially connected in an annular shape through a refrigerant pipe; an outdoor blower that blows air to the heat source-side heat exchanger; a use-side circuit in which a conveyance pump for conveying heat medium, the intermediate heat exchanger, and a use-side heat exchanger are sequentially connected in an annular shape through a heat medium pipe; and an electrical box composed of a control board for controlling operation of the compressor, the expansion device, and the outdoor blower, and power supply parts, wherein the heat source-side circuit is charged with flammable refrigerant, the use-side circuit is charged with the heat medium, the flammable refrigerant and the heat medium flow in the intermediate heat exchanger, the heat medium pipe has a gas discharge device consisting of at least an air vent valve or a pressure relief valve, the gas discharge device is housed in a space C, and the space C and the electrical box are isolated by at least one or more partition walls.
2. The heat medium circulation device according to claim 1, wherein the partition walls includes a first partition wall, a second partition wall and a third partition wall, a housing of the electrical box is the first partition wall, a space A where the compressor is installed and a space B where the electrical box is arranged are isolated by the second partition wall, the space A and the space C are isolated by the third partition wall, and the electrical box and the space C are isolated by the first partition wall, the second partition wall, and the third partition wall.
3. The heat medium circulation device according to claim 2, wherein the electrical box is arranged above in the space B, and the space C is arranged below in the space A.
4. The heat medium circulation device according to claim 2, wherein the space A, the space B and the space C are formed in an outdoor unit, vents are provided in the space C, and the vents introduce air outside of the outdoor unit into the space C and discharge air inside the space C to the outside of the outdoor unit, and the vents do not communicate the space C with the space A, and do not communicate the space C with the space B.
5. The heat medium circulation device according to claim 2, wherein the space A, the space B and the space C are formed in an outdoor unit, the gas discharge device has a communication pipe that discharges gas, and the communication pipe discharges the gas to the outside of the outdoor unit without passing through the space A and the space B.
Citation Information
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