REFRIGERANT LEAK DETECTION SYSTEM

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)

This US Non-Provisional Patent Application relies on and claims priority to Japanese Patent Application No. 2024-098111, filed on Jun. 18, 2024, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

An embodiment of the invention relates to a refrigerant leak detection system for detecting refrigerant leaks from an air conditioning system.

BACKGROUND OF THE INVENTION

For example, as disclosed in Japanese Patent No. 7466061, a system configured such that a leakage of refrigerant used in a refrigeration cycle of an air conditioning system into the interior can be detected has been considered.

In this type of system, the refrigerant detection sensor that detects leaking refrigerant may be integrated with an alarm that gives an alarm when a leak is detected and placed outside the air conditioner, or it may be placed inside the air conditioner. In either form of arrangement, the refrigerant detection sensor is operated by power supplied from a commercial power source. However, with this conventional configuration, the refrigerant detection sensor cannot operate in the event of a power failure.

The embodiment relates to a refrigerant leak detection system that detects a refrigerant leak from an air conditioning system and provides a technical proposal that enables detection of leaking refrigerant even in the event of a power failure.

SUMMARY OF THE INVENTION

A refrigerant leak detection system according to an embodiment is a system that detects a refrigerant leak from an air conditioning system, the system including a detection alarm having a detection unit that detects leaking refrigerant and an alarm unit that alerts when the detection unit detects a refrigerant leak, a power feed adapter having a main power feed unit that supplies power to the detection alarm, and a sub power supply unit that is connected to the power feed adapter, wherein the power feed adapter supplies power to the detection alarm from the sub power supply unit if the main power supply unit becomes unable to supply power to the detection alarm.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram schematically showing a configuration example of a refrigerant leak detection system according to an embodiment; and

FIG. 2 is a block diagram schematically showing a configuration example in which the refrigerant leak detection system according to the embodiment is applied to an air conditioning system.

DESCRIPTION OF EMBODIMENT(S) OF THE INVENTION

An embodiment relating to a refrigerant leak detection system is described hereinafter with reference to drawings. A refrigerant leak detection system 100 illustrated in FIG. 1 is a system that detects a refrigerant leak from an air conditioning system 200 and includes a detection alarm 300 and a power feed adapter 400. The detection alarm 300 and the power feed adapter 400 are communicably connected to each other by a communication line L1. The concept of communication in the present disclosure includes not only transmission and reception of various signals and data but also transmission and reception of power.

The detection alarm 300 includes a sensor board 302 and an alarm board 303 in a housing 301 that forms its outline. The sensor board 302 and the alarm board 303 are communicably connected to each other by a communication line L2.

The sensor board 302 includes a refrigerant detection sensor 304 for detecting refrigerant leaking from the air conditioning system 200. The refrigerant detection sensor 304 is an example of a detection unit. The refrigerant detection sensor 304 is configured by, for example, a refrigerant gas sensor capable of detecting gaseous refrigerant leaking into the air.

The alarm board 303 includes an optical alarm unit 305 and an audible alarm unit 306. The optical alarm unit 305 and the audible alarm unit 306 are both examples of an alarm unit. The optical alarm unit 305 includes an element capable of emitting light such as a light emitting diode (LED), for example, and is capable of alarming in a visual manner by outputting light. The audible alarm unit 306 includes an element capable of emitting sound such as a buzzer, for example, and is capable of alarming in an auditory manner by outputting sound.

The detection alarm 300 includes a control circuit, not shown, that controls overall operations of the detection alarm 300. The detection alarm 300 is configured to alert through at least one of the optical alarm unit 305 and the audible alarm unit 306 when the refrigerant detection sensor 304 detects a refrigerant leak.

The power feed adapter 400 includes a power supply board 402 within the housing 401 that forms its outline. The power supply board 402 includes a commercial power supply unit 403 and a battery power supply unit 404 for supplying power to the detection alarm 300. The commercial power supply unit 403 can supply power obtained from, for example, a commercial power source 405 to the detection alarm 300. The commercial power source 405 is an example of a main power supply unit.

A battery kit 406 is removably connected to the battery power supply unit 404. The battery kit 406 is an example of a sub power supply unit. The battery kit 406 includes, for example, a secondary battery such as a lithium-ion battery or a nickel-metal hydride battery, or a capacitor, and is capable of storing and discharging electricity. The battery kit 406 may be located outside the housing 401 or inside the housing 401.

The power feed adapter 400 includes a control circuit, not shown, that controls overall operations of the power feed adapter 400. The power feed adapter 400 is configured to supply power to the detection alarm 300 from the battery kit 406 by the battery power supply unit 404 when the commercial power supply unit 403 is unable to supply power from the commercial power source 405 to the detection alarm 300 due to, for example, power failure.

As illustrated in FIG. 2, the air conditioning system 200 is configured with a plurality of indoor units 202 [A], 202 [B] for one outdoor unit 201. The air conditioning system 200 includes a refrigeration cycle that includes an outdoor heat exchanger, not shown, included in the outdoor unit 201, an indoor heat exchanger, not shown, included in each of the plurality of indoor units 202 [A], 202 [B], refrigerant pipes, not shown, that circulate refrigerant, a compressor, not shown, that compresses refrigerant, and an expansion valve, not shown, that expands the refrigerant.

The air conditioning system 200 further includes a shutoff device 203 [A] that shuts off supply of refrigerant to the indoor unit 202 [A] and a shutoff device 203 [C] that shuts off supply of refrigerant to the indoor unit 202 [B]. The shutoff device 203 [A] and shutoff device 203 [C] are interposed in a portion of the refrigerant piping that constitutes the refrigeration cycle between the outdoor unit 201 and the indoor units 202 [A], 202 [B], not shown.

In the configuration example shown in FIG. 2, the indoor unit 202 [A] and the shutoff device 203 [A] are located in a room R [A]. The indoor unit 202 [B] is located in a room R [B]. The shutoff device 203 [C] is located in a room R [C].

A plurality of refrigerant leak detection systems 100 [B], 100 [C] are connected to the air conditioning system 200. The refrigerant leak detection systems 100 [B] and 100 [C] are both connected to the indoor unit 202 [B]. However, the detection alarm 300 [B] of the refrigerant leak detection system 100 [B] is located in the room R [B]. On the other hand, the detection alarm 300 [C] of the refrigerant leak detection system 100 [C] is located in the room R [C].

The refrigerant leak detection system 100 [B], in which the detection alarm 300 [B] is located in the room R [B], has a predetermined association, or linkage, to the indoor unit 202 [B]. On the other hand, the refrigerant leak detection system 100 [C], in which the detection alarm 300 [C] is located in room the room R [C], does not have a predetermined linkage to the indoor unit 202 [B].

The predetermined linkage can be achieved, for example, by operating a link setting switch, not shown, provided on the power feed adapter 400 [B] of the refrigerant leak detection system 100 [B]. That is, in The embodiment, the link setting switch, not shown, provided on the power feed adapter 400 [B] of the refrigerant leak detection system 100 [B] is operated, but the link setting switch, not shown, provided on the power feed adapter 400 [C] of the refrigerant leak detection system 100 [C] is not operated. Therefore, the refrigerant leak detection system 100 [B] is linked to the indoor unit 202 [B], but the refrigerant leak detection system 100 [C] is not linked to the indoor unit 202 [B].

The refrigerant leak detection system 100 [B], which has a predetermined linkage to the indoor unit 202 [B], closes the shutoff device 203 [C] that shuts off the supply of refrigerant to the indoor unit 202 [B] when a refrigerant leak from the linked indoor unit 202 [B] is detected by the detection alarm 300 [B]. This stops the supply of refrigerant to the indoor unit 202 [B] and can suppress refrigerant leak in the room R [B]. The detection alarm 300 [B] also provides optical and audible alarms to report that a refrigerant leak is occurring in the room R [B].

The refrigerant leak detection system 100 [C], which does not have a predetermined linkage to the indoor unit 202 [B] stops operation of the entire air conditioning system 200 when a refrigerant leak from a component other than the indoor unit 202 [B] linked to the refrigerant leak detection system 100 [B], in this case, from the shutoff device 203 [C], is detected by the detection alarm 300 [C]. This stops the circulation of refrigerant in the air conditioning system 200 and can prevent a refrigerant leak in the room R [C]. The detection alarm 300 [C] also provides optical and audible alarms to report that a refrigerant leak is occurring in the room R [C].

A central alarm 500 is also connected to the air conditioning system 200. The central alarm 500 is located in a central control room R [D], which is different from rooms R [A], R [B], and R [C]. The central alarm 500, like the detection alarm 300, is equipped with a light alarm section capable of alarming in a visual manner and a sound alarm section capable of alarming in an auditory manner. The central alarm 500 is connected to the outdoor unit 201 of the air conditioning system 200 via an adapter 501.

When a refrigerant leak is detected by the detection alarm 300 [B], the refrigerant leak detection system 100 [B] transmits a leak occurrence signal indicating that a refrigerant leak is occurring in the room R [B] to the central alarm 500 via the indoor unit 202 [B], indoor unit 202 [A] and outdoor unit 201. This allows the central alarm 500 to report that a refrigerant leak is occurring in the room R [B].

When a refrigerant leak is detected by the detection alarm 300 [C], the refrigerant leak detection system 100 [C] transmits a leak occurrence signal indicating that a refrigerant leak is occurring in the room R [C] to the central alarm 500 via the indoor unit 202 [B], indoor unit 202 [A] and outdoor unit 201. This allows the central alarm 500 to report that a refrigerant leak is occurring in the room R [C].

According to the refrigerant leak detection system 100 illustrated above, the power feed adapter 400 supplies power to the detection alarm 300 from the battery kit 406 by the battery power supply unit 404 when power supply from the commercial power source 405 to the detection alarm 300 is disabled. According to this configuration example, even if, for example, a power failure occurs and the supply of power from the commercial power source 405 to the detection alarm 300 is disabled, the power supplied from the battery kit 406 can operate the refrigerant detection sensor 304 and maintain the state in which the refrigerant leaking from the air conditioning system 200 can be detected.

According to the refrigerant leak detection system 100, when a refrigerant leak from the indoor unit 202 to which a predetermined linkage is made is detected by the detection alarm 300, the shutoff device 203 that shuts off the supply of refrigerant to the indoor unit 202 is closed. According to this configuration example, it is possible to shut off the supply of refrigerant to the indoor unit 202 that has a high possibility of a refrigerant leak, that is, to pinpoint the supply of refrigerant to the indoor unit 202 that is likely to be the cause of the refrigerant leak.

According to the refrigerant leak detection system 100, if a refrigerant leak from one other than the indoor unit 202 having a predetermined linkage, in this case, from the shutoff device 203 is detected by the detection alarm 300, the entire air conditioning system 200 will stop operating.

Here, even if a refrigerant leak from the shutoff device 203 could be detected, it is difficult to determine whether the leak is occurring upstream or downstream of the shutoff device 203. If a refrigerant leak is occurring upstream of the shutoff device 203, closing that shutoff device 203 will not stop the refrigerant leak. Therefore, if a refrigerant leak from one other than the indoor unit 202 having a predetermined linkage is detected by the detection alarm 300, the entire air conditioning system 200 can be stopped so as to prevent further refrigerant leakage, no matter at which position the refrigerant leak is occurring.

If the indoor unit 202 [B] and the shutoff device 203 [C] are located relatively close to each other, the single refrigerant leak detection system 100 may be used to detect refrigerant leaks from these indoor units 202 [B] and shutoff device 203 [C].

According to the refrigerant leak detection system 100, the detection alarm 300 and power feed adapter 400 are provided as separate and independent components, which allows for improved flexibility in the installation of the detection alarm 300 and power feed adapter 400. It also allows improved freedom in design of the detection alarm 300 and power feed adapter 400, making each of them smaller and lighter. The refrigerant leak detection system 100 may be configured with the detection alarm 300 and the power feed adapter 400 in the same housing.

According to the refrigerant leak detection system 100, the system can be operated by a power supply system different from the power supply system of the air conditioning system 200 because it includes a dedicated power feed adapter 400. Therefore, even if an abnormality occurs in the power supply system of the air conditioning system 200, power can continue to be supplied to the refrigerant leak detection system 100, and the system will remain capable of detecting refrigerant leaks and providing alarms.

It should be noted that the embodiment is not limited to the aforementioned one embodiment, and various changes, extensions and so on can be made thereto without departing from the spirit and scope of the present invention. For example, communication between the refrigerant leak detection system 100 and the air conditioning system 200 and between the refrigerant leak detection system 100 and the shutoff device 203 may be wired or wireless communication.

The link setting switch that links the refrigerant leak detection system 100 and the indoor unit 202 may be provided in the detection alarm 300, in the power feed adapter 400, or in the indoor unit 202 instead of the refrigerant leak detection system 100.

How the refrigerant leak detection system 100 and the indoor unit 202 are linked may be set in such a way that, for example, a remote control unit or the like, which is provided so as to be capable of remotely operating the refrigerant leak detection system 100, is operated to make a setting. How the refrigerant leak detection system 100 and the indoor unit 202 are linked may be set in such a way that, for example, the same address number or an associated address number is assigned to the refrigerant leak detection system 100 and the indoor unit 202.

How the refrigerant leak detection system 100 and indoor unit 202 are linked may, for example, be achieved in such a way that different wiring configurations are used between the case of making a link and the case of not making a link. To be more specific, for example, it is conceivable to set in such a way that in a wiring configuration with which the refrigerant leak detection system 100 and the indoor unit 202 are directly connected without other components therebetween, they are linked, and, in a wiring configuration with which the refrigerant leak detection system 100 and indoor unit 202 are indirectly connected through other components, they are not linked.

The refrigerant leak detection system 100 does not necessarily have to be linked to the indoor unit 202. Also, for indoor units 202 that are not linked to the refrigerant leak detection system 100, a safety device separate from the refrigerant leak detection system 100 may be installed, for example.

Also, the detection alarm 300 may further be configured to alarm by the optical alarm unit 305 or the audible alarm unit 306 when an abnormality occurs in the communication between the air conditioning system 200 and the power feed adapter 400. According to this configuration example, when an abnormality occurs in the operation of the air conditioning system 200 for some reason, for example, when the power supply to the air conditioning system 200 is disabled due to a power failure or when the communication line connecting the air conditioning system 200 and the power feed adapter 400 is disconnected, the detection alarm 300 can report that an abnormality has occurred in the operation of the air conditioning system 200.

Also, the detection alarm 300 may further be configured to alert by the optical alarm unit 305 and the audible alarm unit 306 when the power supply from the commercial power source 405 is disabled, for example, due to a power failure. That is, according to the refrigerant leak detection system 100 of the present disclosure, the detection alarm 300 can be operated by power supply from the battery kit 406 when the power supply from the commercial power source 405 is disabled. Therefore, for example, if an abnormality occurs in the power supply system from the commercial power source 405 for some reason, the detection alarm 300 can report it.

Also, the detection alarm 300 may further be configured to alarm by the optical alarm unit 305 or the audible alarm unit 306 when an abnormality occurs in communication with the refrigerant detection sensor 304. According to this configuration example, if an abnormality occurs in the refrigerant detection sensor 304 for some reason, for example, if the refrigerant detection sensor 304 fails or if the communication line L2 is disconnected, the detection alarm 300 can report that an abnormality has occurred through the refrigerant detection sensor 304.

Also, the detection alarm 300 may further be configured to alarm by the optical alarm unit 305 or the audible alarm unit 306 when a failure signal is received as a predetermined signal from the refrigerant detection sensor 304. According to this configuration example, for example, if a failure occurs in the refrigerant detection sensor 304 for some reason, it can be reported by the detection alarm 300.

The refrigerant leak detection system 100 may further be configured to perform a lifetime determination to determine whether the refrigerant detection sensor 304 is normal or not based on the total energized time to the refrigerant detection sensor 304. According to this configuration example, it is possible to indicate when to inspect or replace the refrigerant detection sensor 304 according to the age of use and deterioration of the refrigerant detection sensor 304, thereby avoiding the continued use of a refrigerant detection sensor 304 that is not working properly.

The refrigerant leak detection system 100 may further be equipped with a monitoring function that monitors the communication status with the air conditioning system 200, and may be configured to switch the monitoring function between enabled and disabled states. According to the refrigerant leak detection system 100 with the monitoring function switched to the enabled state, if an abnormality occurs in the operation of the air conditioning system 200 for some reason, it can be reported. On the other hand, according to the refrigerant leak detection system 100 with the monitoring function switched to the disabled state, there is no processing load to monitor the communication status with the air conditioning system 200, so resources can be concentrated on handling refrigerant leak detection and alarms. In other words, the refrigerant leak detection system 100 can be operated in a so-called “stand-alone” form, allowing the system to specialize in handling refrigerant leak detection and alarms.

How the monitoring function is switched between the enabled and disabled states may be, for example, by operating a dip switch provided in the detection alarm 300 or power feed adapter 400, or may be in any other way.

Also, the detection alarm 300 may be configured to change its voltage state between alarming and non-alarming states, and to transmit the voltage state to the air conditioning system 200 or the central alarm 500 via an output line, not shown. According to this configuration example, even when the refrigerant leak detection system 100 is operated in a so-called “stand-alone” configuration, it can inform the air conditioning system 200 or central alarm 500 whether or not it is alarming, in other words, whether or not a refrigerant leak is occurring.

The refrigerant leak detection system 100 may be configured with a backup power system instead of or in addition to the battery kit 406.

One shutoff device 203 may be provided for one indoor unit 202, or one may be provided for a plurality of indoor units 202. In a configuration with one shutoff device 203 for a plurality of indoor units 202, the shutoff device 203 should be closed when a refrigerant leak is detected from any one of the plurality of indoor units 202.

The air conditioning system 200 may have a configuration in which the outdoor unit 201 and the indoor unit 202 are connected by three pipes and heat can be recovered and reused, referred to as a “heat recovery system,” or a configuration in which the outdoor unit 201 and the indoor unit 202 are connected by two pipes, referred to as a “heat pump system.

While embodiments of the present invention have been described above, these embodiments have been presented only for illustration purpose and are not intended to limit the scope of the invention herein. These inventive embodiments can be implemented in other various forms, and various omission, replacement, changes and so on can be performed without departing from the spirit of the present invention. These embodiments and variations are encompassed in the scope and spirit of the invention and are encompassed in the invention recited in claims and the scope of the equivalents.