Refrigerant Leak Detection System

The refrigerant leak detection system addresses inefficiencies in existing systems by using a single refrigerant detection sensor and switching device to monitor multiple locations, achieving efficient and rapid leak detection.

JP7654338B2Active Publication Date: 2025-04-01NTT FACILITIES INC
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Patent Information

Application Number
JP2022019613
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2022-02-10
Publication Date
2025-04-01
Estimated Expiration
2042-02-10

AI Technical Summary

Technical Problem

Existing refrigerant leak detection systems require the same number of refrigerant detection sensors as monitoring locations, making them inefficient for monitoring multiple locations with a smaller number of sensors.

Method used

A refrigerant leak detection system that uses a refrigerant detection sensor and switching device to monitor multiple locations by switching between two sampling tubes, allowing for detection of refrigerant leaks at multiple points with fewer sensors.

Benefits of technology

Enables efficient monitoring of multiple refrigerant leak locations using fewer sensors, allowing for quicker detection and identification of leakages compared to traditional systems.

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Abstract

To disclose one example of a refrigerant leakage detection system capable of monitoring a plurality of monitoring portions by using a smaller number of refrigerant detection sensors than that of the monitoring portions.SOLUTION: A refrigerant leakage detection system 10 enables switching between a case where the atmosphere is guided to a refrigerant detection sensor 11 through a first sampling tube 12 and a case where the atmosphere is guided to the refrigerant detection sensor 11 through a second sampling tube 13. This enables monitoring of a plurality of monitoring portions by using a smaller number of refrigerant detection sensors 11 than that of the monitoring portions. The first sampling tube 12 and the second sampling tube 13 are atmosphere introduction tubes for guiding the atmosphere present at a specific portion of a refrigeration machine 1 to the refrigerant detection sensor 11. A suction port of the first sampling tube 12 and a suction port of the second sampling tube 13 are opened at different portions.SELECTED DRAWING: Figure 1
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Description

[Technical field]

[0001] The present disclosure relates to a refrigerant leak detection system for detecting whether or not a refrigerant leak has occurred from a refrigerator. [Background technology]

[0002] For example, in the refrigerant leakage detection system described in Patent Document 1, refrigerant detection sensors are arranged at multiple locations to detect refrigerant leaking from a refrigerator. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. WO2019 / 038797 Summary of the Invention [Problem to be solved by the invention]

[0004] The refrigerant leak detection system described in Patent Document 1 requires the same number of refrigerant detection sensors as the locations to be detected (hereinafter referred to as monitoring locations). In view of this point, the present disclosure discloses an example of a refrigerant leak detection system that can monitor multiple monitoring locations with fewer refrigerant detection sensors than the number of monitoring locations. [Means for solving the problem]

[0005] It is desirable for a refrigerant leakage detection system for detecting whether or not a refrigerant leak has occurred from the refrigerator (1) to include at least one of the following components, for example.

[0006] That is, the components are a refrigerant detection sensor (11) that detects refrigerant contained in the air, a first sampling pipe (12) that guides the atmosphere at a specific location of the refrigerator (1) to the refrigerant detection sensor (11), a second sampling pipe (13) that guides the atmosphere at a location of the refrigerator (1) other than the specific location to the refrigerant detection sensor (11), a switching device (14) that switches between directing the atmosphere to the refrigerant detection sensor (11) through the first sampling pipe (12) and directing the atmosphere to the refrigerant detection sensor (11) through the second sampling pipe (13), and an alarm unit (15A) that issues an alarm when a refrigerant is detected by the refrigerant detection sensor (11).

[0007] As a result, by switching between introducing the atmosphere to the refrigerant detection sensor (11) through the first sampling pipe (12) and introducing the atmosphere to the refrigerant detection sensor (11) through the second sampling pipe (13), it is possible to monitor multiple monitoring locations with a smaller number of refrigerant detection sensors (11) than the number of monitoring locations.

[0008] Incidentally, the symbols in the above parentheses are examples showing the corresponding relationship with the specific configurations etc. described in the embodiments described below, and the present disclosure is not limited to the specific configurations etc. shown by the symbols in the above parentheses. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing a refrigerant leakage detection system according to a first embodiment. [Diagram 2] 4 is an example of a flowchart showing the operation of the refrigerant leakage detection system according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The following "embodiment of the invention" shows an example of an embodiment that falls within the technical scope of the present disclosure. In other words, the invention-specific matters described in the claims are not limited to the specific configurations and structures shown in the following embodiment.

[0011] At least one of each of the components or parts described with a reference symbol is provided, unless otherwise specified by "one". In other words, unless otherwise specified by "one", two or more of the components may be provided. The air conditioner disclosed in this disclosure includes at least the components or parts described with a reference symbol, as well as the structural parts shown in the drawings.

[0012] (First embodiment) <1. Overview of the refrigerant leak detection system (see Figure 1)> In this embodiment, the refrigerant leakage detection system according to the present disclosure is applied to a refrigerant leakage detection system for detecting whether or not a refrigerant leak has occurred from a refrigerator 1 for an air conditioner.

[0013] The refrigerator 1 according to this embodiment is a vapor compression refrigerator including a compressor 2, a radiator 3, a pressure reducer 4, and an evaporator 5. The compressor 2 compresses the low-pressure gas-phase refrigerant flowing out from the evaporator 5. The radiator 3 cools the high-pressure refrigerant discharged from the compressor 2 and having an increased temperature.

[0014] The pressure reducer 4 reduces the pressure of the refrigerant flowing out from the radiator 3. The pressure reducer 4 according to this embodiment is configured with a thermostatic expansion valve. The thermostatic expansion valve automatically adjusts the opening degree (degree of pressure reduction) so that the degree of superheat of the refrigerant at the outlet side of the evaporator 5 becomes a predetermined value.

[0015] The evaporator 5 generates refrigeration capacity, that is, cold heat, by evaporating the liquid-phase refrigerant decompressed by the pressure reducer 4. Specifically, the evaporator 5 exchanges heat between the refrigerant and air to be supplied to the space to be air-conditioned, thereby cooling the air.

[0016] <2. Refrigerant leak detection system> 2.1 Configuration of refrigerant leak detection system (see Figure 1) The refrigerant leak detection system 10 at least includes a refrigerant detection sensor 11, a first sampling pipe 12, a second sampling pipe 13, a switching device 14, and a refrigerant leak monitoring device 15. The refrigerant detection sensor 11 is a detector that detects refrigerant contained in the air.

[0017] The first sampling pipe 12 and the second sampling pipe 13 are atmosphere introduction pipes that introduce the atmosphere present at a specific location in the refrigerator 1 to the refrigerant detection sensor 11. The suction port of the first sampling pipe 12 and the suction port of the second sampling pipe 13 open at different locations.

[0018] In other words, the atmosphere led to the refrigerant detection sensor 11 through the first sampling pipe 12 and the atmosphere led to the refrigerant detection sensor 11 through the second sampling pipe 13 are atmospheres at different locations.

[0019] In this embodiment, the first sampling pipe 12 guides, for example, the atmosphere existing around the radiator 3 to the refrigerant detection sensor 11. The second sampling pipe 13 guides, for example, the atmosphere existing around the evaporator 5 to the refrigerant detection sensor 11.

[0020] The switching device 14 is a device for switching between guiding the atmosphere to the refrigerant detection sensor 11 through the first sampling pipe 12 and guiding the atmosphere to the refrigerant detection sensor 11 through the second sampling pipe 13 .

[0021] The switching device 14 according to this embodiment is composed of on-off valves 14A, 14B, the same number as the sampling pipes. The on-off valve 14A (hereinafter referred to as the first on-off valve 14A) controls the communication state between the first sampling pipe 12 and the refrigerant detection sensor 11.

[0022] The on-off valve 14B (hereinafter referred to as the second on-off valve 14B) controls the communication state between the second sampling pipe 13 and the refrigerant detection sensor 11. The fan 14C is an aspirator for sucking in the atmosphere.

[0023] The refrigerant leakage monitoring device 15 controls the operation of the switching device 14, and also has an alarm unit 15A. That is, an output signal of the refrigerant detection sensor 11 is input to the refrigerant leakage monitoring device 15. Then, the alarm unit 15A issues an alarm when the refrigerant detection sensor 11 detects refrigerant.

[0024] The refrigerant leakage monitoring device 15 is configured with a CPU, a ROM, and a microcomputer having a ROM, etc. The refrigerant leakage monitoring device 15 controls the switching device 14 and the alarm unit 15A by software being executed by the CPU. The software is stored in advance in a non-volatile storage unit such as a ROM.

[0025] <2.2 Control of switching devices, etc.> <Control Overview> The refrigerant leakage monitoring device 15 monitors for refrigerant leakage by opening both the first on-off valve 14A and the second on-off valve 14B. When the refrigerant detection sensor 11 detects a refrigerant leak, the refrigerant leakage monitoring device 15 alternately closes either the first on-off valve 14A or the second on-off valve 14B.

[0026] In other words, refrigerant leakage monitoring device 15 switches at predetermined time intervals between directing the atmosphere to refrigerant detection sensor 11 through first sampling pipe 12 and directing the atmosphere to refrigerant detection sensor 11 through second sampling pipe 13. Hereinafter, this operation is referred to as switching control.

[0027] When the refrigerant leakage monitoring device 15 is executing switching control, it executes a leak location identification function that identifies a sampling tube (hereinafter referred to as a leak detection tube) that is connected to the refrigerant detection sensor 11 when refrigerant is detected.

[0028] Next, the refrigerant leak monitoring device 15 closes the on-off valve installed in the identified leak detection tube to maintain the leak detection tube in a non-communicating state and issues a warning that a refrigerant leak has occurred around the suction port of the leak detection tube.

[0029] The above warning is sent to the person in charge of managing the chiller 1 (hereinafter referred to as the manager). Upon receiving the warning, the manager takes appropriate measures against the refrigerant leakage, and then instructs the refrigerant leakage monitoring device 15 to inform the user that the measures have been completed.

[0030] <Control details (see Fig. 2)> 2 is an example of a flowchart of the operation control. The operation control is started in conjunction with the start-up of the refrigerator 1. When the operation control is started, the refrigerant leakage monitoring device 15 first monitors for refrigerant leakage (S3) with the first on-off valve 14A and the second on-off valve 14B open (S1).

[0031] Then, when a refrigerant leakage is detected (S3: YES), the refrigerant leakage monitoring device 15 keeps the second on-off valve 14B closed for a predetermined time (S5), and determines whether a refrigerant leakage has been detected (S7).

[0032] If a refrigerant leak is detected (S7: YES), the refrigerant leak monitoring device 15 issues a report that a refrigerant leak has occurred and the location of the leak (S13), and closes the on-off valve provided in the leak detection tube to maintain the leak detection tube in a non-communicating state (S15).

[0033] If no refrigerant leakage is detected (S7: NO), the refrigerant leakage monitoring device 15 closes the first on-off valve 14A and then opens the second on-off valve 14B (S9), and determines whether or not a refrigerant leakage has been detected (S11).

[0034] If a refrigerant leakage is detected (S11: YES), the refrigerant leakage monitoring device 15 executes S13 and S15. If a refrigerant leakage is not detected (S11: NO), the refrigerant leakage monitoring device 15 executes S1 again.

[0035] When the on-off valve provided in the leak detection tube is closed (S15), the refrigerant leakage monitor 15 continues to monitor for refrigerant leakage in the atmosphere introduced via a sampling tube other than the leak detection tube (S17).

[0036] <3. Features of the refrigerant leak detection system according to this embodiment> In the refrigerant leak detection system 10 of this embodiment, by switching between directing the atmosphere to the refrigerant detection sensor 11 through the first sampling pipe 12 and directing the atmosphere to the refrigerant detection sensor 11 through the second sampling pipe 13, it is possible to monitor multiple monitoring locations using a smaller number of refrigerant detection sensors 11 than the number of monitoring locations.

[0037] In the refrigerant leak detection system 10 according to this embodiment, the presence or absence of refrigerant leaks is monitored with all sampling tubes connected to the refrigerant detection sensor 11, and when a refrigerant leak is detected in this state, switching control is executed.

[0038] This makes it possible to detect a refrigerant leak more quickly than in a configuration in which switching control is performed without connecting all of the sampling pipes to the refrigerant detection sensor 11.

[0039] That is, for example, when the first sampling pipe 12 is connected and the second sampling pipe 13 is not connected, even if a refrigerant leak occurs on the suction side of the second sampling pipe 13, the refrigerant leakage monitoring device 15 cannot detect the refrigerant leak until the connection state is switched.

[0040] In contrast, in this embodiment, the presence or absence of refrigerant leakage is monitored with all sampling pipes in communication with the refrigerant detection sensor 11. Misalignment Even if a refrigerant leak occurs at this location, the refrigerant leak monitoring device 15 can quickly detect the refrigerant leak.

[0041] (Other embodiments) In the above embodiment, since there are two monitoring locations, two sampling pipes are provided. However, the present disclosure is not limited to this. That is, the present disclosure is also applicable to a configuration in which there are three or more monitoring locations, for example. The number of sampling pipes is the same as the number of monitoring locations.

[0042] The switching device 14 according to the embodiment described above is configured with the same number of on-off valves as the number of sampling pipes. However, the present disclosure is not limited to this. That is, in the present disclosure, for example, the switching device 14 may be configured with one or more switching valves.

[0043] In the above-described embodiment, the presence or absence of refrigerant leakage is monitored with all sampling tubes connected to the refrigerant detection sensor 11, and when a refrigerant leakage is detected in this state, switching control is performed to execute the leak location identification function.

[0044] However, the present disclosure is not limited to this. That is, in the present disclosure, for example, the switching control may be performed without connecting all the sampling tubes to the refrigerant detection sensor 11. In other words, the presence or absence of a refrigerant leak and the leak detection tube may be identified by switching the connected sampling tubes at predetermined time intervals.

[0045] In the above-described embodiment, the refrigerator is configured by one refrigerator. However, the present disclosure is not limited to this. That is, the present disclosure may be configured, for example, such that the refrigerator described in the claims is configured by two refrigerators, and the atmosphere around the evaporator of the first refrigerator is introduced to the refrigerant detection sensor 11 by the first sampling pipe 12, and the atmosphere around the evaporator of the second refrigerator is introduced to the refrigerant detection sensor 11 by the second sampling pipe 13.

[0046] Furthermore, the present disclosure is not limited to the above-mentioned embodiments as long as it is consistent with the gist of the disclosure described in the above-mentioned embodiments. Therefore, the present disclosure may be a configuration in which at least two of the above-mentioned embodiments are combined, or a configuration in which any of the components illustrated or the components described with reference numerals in the above-mentioned embodiments are eliminated. [Explanation of symbols]

[0047] 1. Freezer 2. Compressor 3… Heatsink 4… Pressure reducer 5. Evaporator 10... Refrigerant leak detection system 11... Refrigerant detection sensor 12… First sampling tube 13… Second sampling tube 14... Switching device 15... Refrigerant leakage monitoring device 15A… Alarm section

Claims

1. A refrigerant leak detection system for detecting whether or not a refrigerant leak has occurred from a refrigerator, A refrigerant detection sensor that detects refrigerant contained in the air; a first sampling pipe that introduces an atmosphere at a specific location of the refrigerator to the refrigerant detection sensor; a second sampling pipe that introduces an atmosphere at a location different from the specific location of the refrigerator to the refrigerant detection sensor; a switching device for switching between a case where the atmosphere is introduced to the refrigerant detection sensor through the first sampling pipe and a case where the atmosphere is introduced to the refrigerant detection sensor through the second sampling pipe, the switching device having at least a first on-off valve that controls a communication state between the first sampling pipe and the refrigerant detection sensor, and a second on-off valve that controls a communication state between the second sampling pipe and the refrigerant detection sensor; a refrigerant leakage monitoring device capable of controlling the operation of the switching device, the refrigerant leakage monitoring device being capable of performing a leak location identification function of identifying a sampling tube (hereinafter referred to as a leak detection tube) that is in communication with the refrigerant detection sensor when a refrigerant is detected; The refrigerant leakage monitoring device opens both the first and second on-off valves to monitor for refrigerant leakage, and when a refrigerant leakage is detected by the refrigerant detection sensor, closes either the first or second on-off valve alternately at predetermined time intervals, thereby identifying the leak detection tube.

2. A refrigerant leak detection system as described in claim 1, comprising an alarm unit that issues an alarm when refrigerant is detected by the refrigerant detection sensor.

3. A refrigerant leak detection system as described in claim 2, wherein the switching device maintains the leak detection tube in a non-connected state when refrigerant is detected.

Citation Information

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