Ventilation system

Abstract

This system allows for the discharge of refrigerant from the air-conditioned space in the event of a refrigerant leak, thereby reducing costs and enabling the use of smaller ventilation equipment. [Solution] In a building 3 having multiple air-conditioned spaces 2, each of the multiple air-conditioned spaces 2 is equipped with ventilation devices 11-16, and a refrigerant discharge processing unit 7 is provided to perform a refrigerant discharge process by activating the ventilation devices 11 and 12 to discharge the refrigerant when a refrigerant leak is detected in an air-conditioned space 2, the capacity of each ventilation device 11-16 is set to a capacity less than the required ventilation volume when a refrigerant leak occurs, and a connection state switching unit 6 is provided that can switch between a connected state and a disconnected state in which the multiple air-conditioned spaces 2 are connected, and in the refrigerant discharge process, the refrigerant discharge processing unit 7 switches the connection state switching unit 6 to the connected state, making the multiple air-conditioned spaces 2, including the air-conditioned space 2 in which a refrigerant leak was detected, into a single space for refrigerant discharge, and activating the multiple ventilation devices 11 and 12 corresponding to each of the multiple air-conditioned spaces 2 that have become a single space for refrigerant discharge.

Description

Technical Field

[0001] The present invention relates to a ventilation system in a building having a plurality of air-conditioned spaces, in which each of the plurality of air-conditioned spaces is provided with a ventilation device.

Background Art

[0002] In a building having a plurality of air-conditioned spaces, an air-conditioning device having a refrigerant circuit in which a plurality of indoor units and an outdoor unit arranged in each of the plurality of air-conditioned spaces are connected by refrigerant pipes is provided, and by flowing refrigerant through the refrigerant circuit, cooling and heating of the air-conditioned spaces are performed.

[0003] In such an air-conditioning device, since there is a possibility of refrigerant leakage occurring in the refrigerant circuit, a shut-off device for shutting off the supply of refrigerant to the indoor unit is provided when refrigerant leakage occurs. When the refrigerant is flammable or slightly flammable, or when it is non-flammable but has a low limit concentration of toxicity, it is necessary to take separate measures so that the concentration of the refrigerant flowing out into the air-conditioned space does not reach the specified concentration.

[0004] As a countermeasure, conventionally, when detecting refrigerant leakage in an air-conditioned space using a ventilation device installed in the air-conditioned space, a refrigerant discharge process is performed in which the ventilation device is operated to discharge the refrigerant from the air-conditioned space (see, for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Patent documents 1 and 2 describe a ventilation system installed in an air-conditioned space that is used to discharge or agitate refrigerant from the space where a leak has been detected. Therefore, the ventilation system must have a capacity greater than the required ventilation volume when a refrigerant leak occurs. Consequently, a larger capacity is required than the normal ventilation volume needed to ventilate the air-conditioned space, necessitating the installation of a larger ventilation system, which leads to increased costs and larger ventilation systems.

[0007] In light of these circumstances, the main objective of the present invention is to provide a ventilation system that can discharge refrigerant from the air-conditioned space in the event of refrigerant leakage, thereby reducing costs and enabling miniaturization of the ventilation device. [Means for solving the problem]

[0008] The first characteristic configuration of the present invention is that in a building having multiple air-conditioned spaces, each of the multiple air-conditioned spaces is equipped with a ventilation device. The system includes a refrigerant discharge processing unit that, when a refrigerant leak is detected in the air-conditioned space, activates the ventilation device to discharge the refrigerant. The capacity of each ventilation device is set to be less than the required ventilation volume in the event of a refrigerant leak. A connection state switching unit is provided that can be freely switched between a connected state and a non-connected state, which connects multiple air-conditioned spaces. In the refrigerant discharge process, the refrigerant discharge processing unit switches the communication state switching unit to a communication state, thereby making multiple air-conditioned spaces, including the air-conditioned space where refrigerant leakage was detected, into a single space for refrigerant discharge, and activating the multiple ventilation devices corresponding to each of the multiple air-conditioned spaces that have been made into a single space for refrigerant discharge.

[0009] Each ventilation device installed in multiple air-conditioned spaces is set to a capacity less than the required ventilation volume in the event of a refrigerant leak. Therefore, when a refrigerant leak is detected in an air-conditioned space, simply activating the ventilation device corresponding to that space is insufficient to ensure the required ventilation volume in the event of a refrigerant leak.

[0010] Therefore, in this configuration, during refrigerant discharge processing, the communication state switching unit is switched to the communication state, and multiple air-conditioned spaces, including the air-conditioned space for leak detection, are made into a single space for refrigerant discharge, and multiple ventilation devices corresponding to each of the multiple air-conditioned spaces made into a single space for refrigerant discharge are activated. As a result, even if the ventilation device corresponding to the air-conditioned space for leak detection alone has less capacity than the required ventilation volume when a refrigerant leak occurs, by activating multiple ventilation devices, the required ventilation volume when a refrigerant leak occurs in the single space for refrigerant discharge can be secured, and the refrigerant can be discharged from the single space for refrigerant discharge.

[0011] Therefore, instead of installing a ventilation system with a large capacity for refrigerant discharge, a small ventilation system set to a capacity less than the required ventilation volume during a refrigerant leak can be used to discharge refrigerant from the air-conditioned space during a refrigerant leak, thereby reducing costs and allowing for the miniaturization of the ventilation system.

[0012] A second characteristic feature of the present invention is that the communication state switching unit is configured to be able to switch between a communication state and a non-communication state between adjacent air-conditioned spaces.

[0013] According to this configuration, the communication state switching unit only needs to have a configuration that switches between adjacent air-conditioned spaces between connected and disconnected states, thus simplifying the configuration while appropriately switching between connected and disconnected states.

[0014] A third characteristic configuration of the present invention is that the communication state switching unit is configured to be able to switch between a communication state and a non-communication state a communication opening provided in a partition wall that separates adjacent air-conditioned spaces. The advantage of the aforementioned communication opening is that it secures an effective opening area sufficient to treat adjacent air-conditioned spaces as a single space.

[0015] With this configuration, the communication state switching unit can switch between a communication state and a non-communication state simply by opening and closing a communication opening provided in the partition wall, further simplifying the configuration. Moreover, since the communication opening has an effective opening area large enough to treat adjacent air-conditioned spaces as the same space, when the communication opening is opened, adjacent air-conditioned spaces can be appropriately treated as the same space for refrigerant discharge, and refrigerant can be discharged from this same space for refrigerant discharge, thereby ensuring proper refrigerant discharge from the air-conditioned spaces. [Brief explanation of the drawing]

[0016] [Figure 1] This diagram shows the schematic configuration of a ventilation system in a space where no refrigerant leak has been detected. [Figure 2] This diagram shows the schematic configuration of a ventilation system when a refrigerant leak is detected in the air-conditioned space. [Modes for carrying out the invention]

[0017] An embodiment of the ventilation system according to the present invention will be described with reference to the drawings. As shown in Figure 1, this ventilation system 1 is applied to a building 3 such as a hotel that has multiple air-conditioned spaces 2 (rooms). Figure 1 shows six air-conditioned spaces 2, the 1st to 6th air-conditioned spaces 21-26, as an example, but the number of air-conditioned spaces 2 can be changed as appropriate. In building 3, the 1st to 6th air-conditioned spaces 21-26 are arranged adjacent to each other, and adjacent air-conditioned spaces 2 are separated from each other by partition walls 4.

[0018] The ventilation system 1 is provided with ventilation devices 11 - 16 (for example, constant - volume ventilation devices that blow air at a constant volume) for each of a plurality of air - conditioned spaces 2. In FIG. 1, one first - sixth ventilation device 11 - 16 is disposed in each of the first - sixth air - conditioned spaces 21 - 26. The ventilation system 1 is configured to be able to separately switch each of the first - sixth ventilation devices 11 - 16 between an operating state and a non - operating state, and is configured to be able to separately ventilate each of the first - sixth air - conditioned spaces 21 - 26. In FIG. 1, for example, the state in which the first, third, and fifth ventilation devices 11, 13, 15 are switched to the operating state (refer to the arrows) and the first, third, and fifth air - conditioned spaces 21, 23, 25 are being ventilated is shown.

[0019] In this building 3, as shown in FIG. 1, in addition to the ventilation system 1, an air - conditioning device 5 for air - conditioning each of a plurality of air - conditioned spaces 2 is provided. The air - conditioning device 5 includes an outdoor unit (not shown), indoor units 51 disposed in each of a plurality of air - conditioned spaces 2, and a refrigerant circuit in which the outdoor unit and the plurality of indoor units 51 are connected by refrigerant pipes 52. The air - conditioning device 5 can perform cooling and heating of a plurality of air - conditioned spaces 2 by flowing refrigerant between the outdoor unit and the indoor units 51 in the refrigerant circuit through the refrigerant pipes 52.

[0020] In such an air - conditioning device 5, since there is a possibility of refrigerant leakage in the refrigerant circuit, a shut - off device (not shown) for shutting off the supply of refrigerant to the indoor unit 51 is provided when refrigerant leakage occurs.

[0021] In recent years, as the refrigerant in the air - conditioning device 5, for example, the refrigerant has been switched from R410A to a refrigerant with a lower global warming potential such as R32. Along with this, stricter conditions have been set as safety measures when the refrigerant leaks into the air - conditioned space 2.

[0022] Therefore, in this embodiment, safety measures are taken using ventilation systems 1 installed in multiple air-conditioned spaces 2. These safety measures include a communication state switching unit 6 that can switch between a communication state and a non-communication state in which multiple air-conditioned spaces 2 are connected, and a refrigerant discharge processing unit 7 that performs refrigerant discharge processing.

[0023] The communication state switching unit 6 is composed of a damper that opens and closes a communication opening 8 formed in a partition wall 4 that separates adjacent air-conditioned spaces 2, and is configured to allow switching between a connected state and a disconnected state between adjacent air-conditioned spaces 2. As shown in Figure 2, the connected state of the communication state switching unit 6 is shown in white, and as shown in Figures 1 and 2, the disconnected state is shown in black.

[0024] The communication state switching unit 6 is provided for each of the multiple partition walls 4 that divide adjacent air-conditioned spaces 2, and is equipped with first to third communication state switching units 61-63. The communication opening 8 is located on the lower side of the partition wall 4 and has an effective opening area (for example, 0.012 m²) sufficient to treat adjacent air-conditioned spaces 2 as the same space. 2 The above is ensured.

[0025] The refrigerant discharge processing unit 7 performs a refrigerant discharge process by activating the ventilation devices 11-16 to discharge the refrigerant when it detects a refrigerant leak in the air-conditioned space 2. In the refrigerant discharge process, the refrigerant discharge processing unit 7 does not simply activate the ventilation devices 11-16, but as shown in Figure 2, it switches the communication state switching unit 6 to the communication state (the communication state switching unit 6 is shown in white in the figure), thereby treating multiple air-conditioned spaces 2, including the air-conditioned space 2 where the refrigerant leak was detected, as a single space for refrigerant discharge, and activates the multiple ventilation devices 11-16 corresponding to each of the multiple air-conditioned spaces 2 that have been treated as a single space for refrigerant discharge.

[0026] Each of the multiple air-conditioned spaces 2 is equipped with a leak detection unit 9, as shown in Figure 1, which detects refrigerant leakage by detecting the concentration of refrigerant in the air within the air-conditioned space 2. Each of the first to sixth air-conditioned spaces 21 to 26 is equipped with one of the first to sixth leak detection units 91 to 96. This allows for the detection of refrigerant leakage separately in each of the first to sixth air-conditioned spaces 21 to 26.

[0027] Figure 2 shows the state in which refrigerant discharge processing is performed when the second leak detection unit 92 detects a refrigerant leak in the second air-conditioned space 22, while the first, third, and fifth air-conditioned spaces 21, 23, and 25 shown in Figure 1 are being ventilated.

[0028] As shown in gray in Figure 2, when the second leak detection unit 92 detects a refrigerant leak in the second air-conditioned space 22, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the communication state, making the two air-conditioned spaces 2, the second air-conditioned space 22 where the refrigerant leak was detected and the first air-conditioned space 21 adjacent to the second air-conditioned space 22, a single space for refrigerant discharge, and setting the first ventilation device 11 and the second ventilation device 12 corresponding to the two air-conditioned spaces 2 that have become a single space for refrigerant discharge to the operational state. Incidentally, since the first ventilation device 11 is already in the operational state, the refrigerant discharge process continues the operational state of the first ventilation device 11 and switches the second ventilation device 12 from the deactivated state to the operational state.

[0029] As a result, even if the second ventilation device 12 corresponding to the second air-conditioned space 22 for leak detection has less capacity than the required ventilation volume in the event of a refrigerant leak, by operating both the first ventilation device 11 and the second ventilation device 12, the required ventilation volume in the event of a refrigerant leak in the same space for refrigerant discharge (first air-conditioned space 21 and second air-conditioned space 22) can be achieved (for example, 163 m³). 3 It is possible to ensure a minimum of 1 / h and discharge the refrigerant from the same space used for refrigerant discharge.

[0030] Therefore, even if a ventilation device 11-16 with a large capacity for refrigerant discharge is not installed as the ventilation device 11-16, the required ventilation volume in the event of refrigerant leakage (for example, 163 m³) is sufficient. 3 By using ventilation devices 11-16 set to a capacity of less than the required ventilation volume (e.g., 163 m³ / h), refrigerant can be discharged from the air-conditioned space 2 in the event of a refrigerant leak. Therefore, the capacity of each ventilation device 11-16 is set to the required ventilation volume (e.g., 163 m³ / h) in the event of a refrigerant leak. 3 The capacity is set to less than / h, aiming to reduce costs and miniaturize the ventilation device 11-16.

[0031] As shown in Figure 2, when the second leak detection unit 92 detects a refrigerant leak in the second air-conditioned space 22, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the communication state and performs a refrigerant discharge process that activates the first ventilation device 11 and the second ventilation device 12, thereby discharging refrigerant from the first air-conditioned space 21 and the second air-conditioned space 22.

[0032] When the second leak detection unit 92 detects that the concentration of refrigerant in the air in the second air-conditioned space 22 has fallen below the safety set value, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the non-communication state to continue the operation of the first ventilation device 11, and performs a recovery operation to switch the second ventilation device 12 from the operation state to the deactivation state, thereby returning the first, third, and fifth air-conditioned spaces 21, 23, and 25 shown in Figure 1 to a state of ventilation.

[0033] Regarding refrigerant discharge treatment, Figure 2 illustrates the first case in which, of two adjacent air-conditioned spaces 2 (first air-conditioned space 21 and second air-conditioned space 22), refrigerant leakage is detected in the second air-conditioned space 22, which is not being ventilated, while the first air-conditioned space 21 is being ventilated. However, refrigerant leakage may also be detected under other conditions, such as whether or not ventilation is in progress, so the following describes cases other than the first case.

[0034] For example, in the second case, of two adjacent air-conditioned spaces 2 (the first air-conditioned space 21 and the second air-conditioned space 22), if the first air-conditioned space 21 is being ventilated, a refrigerant leak may be detected in the first air-conditioned space 21 while it is being ventilated.

[0035] In this second case, as in the first case in Figure 2, as part of the refrigerant discharge process, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the communication state, making the two air-conditioned spaces 2, the first air-conditioned space 21 where refrigerant leakage was detected and the second air-conditioned space 22 adjacent to the first air-conditioned space 21, into a single space for refrigerant discharge. For the first ventilation device 11 and the second ventilation device 12 corresponding to the two air-conditioned spaces 2 that have been made into a single space for refrigerant discharge, the operation state of the first ventilation device 11 is continued, and the operation state of the second ventilation device 12 is switched from the stopped state to the operating state.

[0036] In this second case, when the first leak detection unit 91 detects that the concentration of refrigerant in the air in the first air-conditioned space 21 has fallen below the safety set value, the refrigerant discharge processing unit 7 performs a recovery operation. In this recovery operation, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to a non-communication state to continue the operation of the first ventilation device 11, switches the second ventilation device 12 from the operation state to the deactivation state, and returns the first, third, and fifth air-conditioned spaces 21, 23, and 25 shown in Figure 1 to a state of ventilation.

[0037] In a third case, when both of two adjacent air-conditioned spaces 2 (the first air-conditioned space 21 and the second air-conditioned space 22) are being ventilated, a refrigerant leak may be detected in one of the air-conditioned spaces 2.

[0038] In this third case, as part of the refrigerant discharge process, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the communication state, making the two air-conditioned spaces 2, the first air-conditioned space 21 and the second air-conditioned space 22, into a single space for refrigerant discharge, and continuing the operation of the first ventilation device 11 and the second ventilation device 12 corresponding to each of the two air-conditioned spaces 2 that have been made into a single space for refrigerant discharge.

[0039] In this third case, when the refrigerant discharge processing unit 7 detects that the concentration of refrigerant in the air in the air-conditioned space 2 where a refrigerant leak was detected has fallen below the safety set value, the refrigerant discharge processing unit 7 performs a reset operation. In this reset operation, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the non-communication state, allowing the operation of the first ventilation device 11 and the second ventilation device 12 to continue, and returning the first ventilation device 11 and the second ventilation device 12 to the operation state in which they were already operating.

[0040] In a fourth case, when both of the two adjacent air-conditioned spaces 2 (the first air-conditioned space 21 and the second air-conditioned space 22) are not being ventilated, a refrigerant leak may be detected in one of the air-conditioned spaces 2.

[0041] In this fourth case, as part of the refrigerant discharge process, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the communication state, making the two air-conditioned spaces 2 a single space for refrigerant discharge, and switches the first ventilation device 11 and the second ventilation device 12 corresponding to each of the two air-conditioned spaces 2 that have become a single space for refrigerant discharge from the stopped state to the operating state.

[0042] In this fourth case, when the refrigerant discharge processing unit 7 detects that the concentration of refrigerant in the air in the air-conditioned space 2 where a refrigerant leak was detected has fallen below the safety set value, the refrigerant discharge processing unit 7 performs a recovery operation. In this recovery operation, the refrigerant discharge processing unit 7 switches the first communication state switching unit 61 to the non-communication state, switching the first ventilation device 11 and the second ventilation device 12 from the operating state to the deactivated state, returning the first ventilation device 11 and the second ventilation device 12 to the deactivated state.

[0043] Thus, in the refrigerant discharge process, when a refrigerant leak is detected in a certain air-conditioned space 2, the refrigerant discharge processing unit 7 switches the communication state switching unit 6 corresponding to that air-conditioned space 2 to a communication state, thereby making two adjacent air-conditioned spaces 2 a single space for refrigerant discharge. The refrigerant discharge processing unit 7 then, regarding the two ventilation devices 11-16 corresponding to the two air-conditioned spaces 2 that have been made a single space for refrigerant discharge, continues their operation if they are already operating, or switches them to an operating state if they are stopped, thereby making both ventilation devices 11-16 operational.

[0044] During the recovery operation, the refrigerant discharge processing unit 7 returns the communication state switching unit 6, which had been switched to the communication state, back to the non-communication state. For the two ventilation devices 11-16 corresponding to the two air-conditioned spaces 2 that are the same space for refrigerant discharge, the ventilation device 11-16, which had been switched to the operating state, is switched back from the operating state to the stopped state.

[0045] [Another embodiment] Other embodiments of the present invention will now be described. Note that the configurations of each embodiment described below are not limited to being applied individually, but can also be applied in combination with the configurations of other embodiments.

[0046] (1) In the above embodiment, in the refrigerant discharge process, the refrigerant discharge processing unit 7 switches one communication state switching unit 6 to a communication state to make the two air-conditioned target spaces 2, the air-conditioned target space 2 where refrigerant leakage was detected and the air-conditioned target space 2 adjacent to it, into a single space for refrigerant discharge. However, for example, the refrigerant discharge processing unit 7 can also switch two communication state switching units 6 to a communication state to make three air-conditioned target spaces 2, the air-conditioned target space 2 where refrigerant leakage was detected and the two air-conditioned target spaces 2 adjacent to it on both sides, into a single space for refrigerant discharge. The number of air-conditioned target spaces 2 to be made into a single space for refrigerant discharge can be changed as appropriate.

[0047] As described above, if the three air-conditioned spaces 2 in which refrigerant leakage was detected, and the two air-conditioned spaces 2 adjacent to it on both sides, are treated as the same space for refrigerant discharge, then three ventilation devices corresponding to each of the three air-conditioned spaces 2 will be activated.

[0048] (2) In the above embodiment, the communication state switching unit 6 switches adjacent air-conditioned spaces 2 between a communication state and a non-communication state. However, for example, the communication state switching unit can also be configured to freely switch between a communication state and a non-communication state between air-conditioned spaces 2 that are not adjacent but are far apart.

[0049] (3) In the above embodiment, the size of the multiple air-conditioned spaces 2 can be set to the same size or to different sizes. The size of each air-conditioned space 2 can be changed as appropriate.

[0050] (4) In the above embodiment, a constant-airflow ventilation device that delivers a constant airflow was given as an example of the ventilation device 11-16, but for example, a variable-airflow ventilation device that can adjust the airflow can also be applied. In this case, in the refrigerant discharge processing, the refrigerant discharge processing unit 7 may not simply set the multiple ventilation devices 11-16 corresponding to each of the multiple air-conditioned spaces 2 that are the same space for refrigerant discharge to an increased airflow such as the maximum airflow before setting them to an operating state. [Explanation of Symbols]

[0051] 1. Ventilation System 2. Spaces to be air-conditioned 3 Buildings 4 partition walls 5 Air conditioner 6. Connectivity state switching section 7. Refrigerant discharge processing unit 8 connecting ports 9. Leak detection unit 11. First ventilation system (ventilation system) 12. Second ventilation system (ventilation system) 13. Third ventilation system (ventilation system) 14. Fourth ventilation system (ventilation system) 15. Fifth ventilation system (ventilation system) 16. Ventilation System No. 6 (Ventilation System)

Claims

1. In a building having multiple air-conditioned spaces, each of the multiple air-conditioned spaces is equipped with a ventilation device. The system includes a refrigerant discharge processing unit that, when a refrigerant leak is detected in the air-conditioned space, activates the ventilation device to discharge the refrigerant. The capacity of each ventilation device is set to be less than the required ventilation volume in the event of a refrigerant leak. A connection state switching unit is provided that can be freely switched between a connected state and a non-connected state, which connects multiple air-conditioned spaces. In the refrigerant discharge process, the refrigerant discharge processing unit switches the communication state switching unit to a communication state, thereby making a plurality of air-conditioned spaces, including the air-conditioned space where refrigerant leakage was detected, into a single space for refrigerant discharge, and activating a plurality of ventilation devices corresponding to each of the plurality of air-conditioned spaces that have been made into a single space for refrigerant discharge.

2. The ventilation system according to claim 1, wherein the communication state switching unit is configured to be able to switch between a communication state and a non-communication state between adjacent air-conditioned spaces.

3. The aforementioned communication state switching unit is configured to be able to switch between a communication state and a non-communication state using a communication opening provided in a partition wall that separates adjacent air-conditioned spaces. The ventilation system according to claim 2, wherein the aforementioned communication opening has an effective opening area sufficient to allow adjacent air-conditioned spaces to be considered as the same space.

Images