JP7742566B2 - Refrigerant Sensor Unit - Google Patents

Description

The present invention relates to a refrigerant sensor unit.

Patent Document 1 discloses a refrigerant detection device that can detect refrigerant leaked into multiple rooms using fewer sensors than the number of rooms to be detected. This refrigerant detection device includes a sensor that can detect refrigerant sealed in the refrigerant piping of an air conditioner, and a casing that houses the sensor. The casing is formed with a first opening that can communicate with the interior of the room, and a second opening that can communicate with the interior of the room to which the first opening can communicate (see, for example, Patent Document 1).

WO2018/163417

The present invention provides a refrigerant sensor unit that can prevent malfunctions in the refrigerant sensor.

The refrigerant sensor unit of the present disclosure comprises a housing attached to a wall surface of an indoor space which is the conditioned space of an air conditioning device, and a refrigerant sensor housed inside the housing, wherein a first side wall forming one side of the housing has a first opening connecting the inside and outside of the housing, and a second side wall different from the first side wall of the housing has a second opening connecting the inside and outside of the housing, the first opening and the second opening are located adjacent to the refrigerant sensor but not facing each other, and the second side wall is positioned at a position which becomes the bottom or one side of the housing when the housing is attached to the wall surface .

The refrigerant sensor unit disclosed herein can prevent static electricity passing through the first opening from discharging to the refrigerant sensor. This prevents malfunction of the refrigerant sensor. Furthermore, by placing the refrigerant sensor near the first opening, leaking refrigerant can be detected quickly. Furthermore, the refrigerant sensor can be installed in a wider variety of mounting positions, and can be installed to more reliably detect refrigerant leaks.

FIG. 1 is a diagram showing the arrangement of a refrigerant sensor unit according to an embodiment of the present invention; Perspective view of the refrigerant sensor unit FIG. 1 is a perspective view of a refrigerant sensor unit with a sheet member omitted; Rear view of the refrigerant sensor unit 3 is a cross-sectional view taken along plane V in FIG. 6 is a cross-sectional view taken along plane VI of FIG.

At the time the inventors arrived at the idea of the present disclosure, there was a refrigerant sensor unit that made it possible to detect, using a refrigerant sensor, refrigerant leaking into a room, which is a space to be conditioned by an air conditioner.
Among such refrigerant sensor units is a so-called external type that is installed in the space to be conditioned and is electrically connected to a control unit of the indoor unit of the air conditioner.
The refrigerant sensor unit also includes a refrigerant sensor and a housing that protects the refrigerant sensor. The housing has an opening that connects the outside of the housing to the refrigerant sensor so that the refrigerant sensor can detect the refrigerant.

However, people may be present in the conditioned space, and these people may bring their fingers or other objects close to the refrigerant sensor unit. If a finger or other object that approaches the refrigerant sensor unit becomes statically charged, the static electricity may be discharged to the refrigerant sensor through the opening in the housing. The inventors discovered this problem, which could cause the refrigerant sensor to malfunction, and have come to form the subject of the present disclosure in order to solve this problem.
Therefore, the present disclosure provides a refrigerant sensor unit that can suppress the occurrence of malfunctions in the refrigerant sensor.
Hereinafter, embodiments will be described in detail with reference to the drawings. However, unnecessary detailed description may be omitted. For example, detailed description of well-known matters or redundant description of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art.
The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment)
1 to 6, the first embodiment will be described. In each figure, the symbol FR indicates the front of the refrigerant sensor unit 10 when it is placed horizontally, the symbol UP indicates the upper side of the refrigerant sensor unit, and the symbol RH indicates the right side of the refrigerant sensor unit. In the following description, all directions are along the direction of the refrigerant sensor unit 10.

[1-1. Configuration]
FIG. 1 is a diagram showing the arrangement of a refrigerant sensor unit 10 according to this embodiment.
The refrigerant sensor unit 10 of this embodiment is a refrigerant leakage detection unit provided in the air conditioning apparatus 1 .
The air conditioner 1 of this embodiment is equipped with a refrigeration cycle formed by a heat exchanger housed in the indoor unit 5, which is the indoor unit, a pressure reducing device such as a compressor and an electronic expansion valve housed in the outdoor unit, and an outdoor heat exchanger provided in the outdoor unit. The air conditioner 1 conditions the indoor space 100, which is the space to be conditioned, by circulating a refrigerant through this refrigeration cycle. The indoor space 100 is a space used by people.

As shown in FIG. 1, an air outlet 6 of the indoor unit 5 is provided on a wall surface 101 of the indoor space 100. Air conditioned by the air conditioning device 1 for the indoor space 100 is blown out from the air outlet 6.

The air conditioning apparatus 1 includes a control unit. The control unit includes a computer having a processor such as a CPU or an MPU, and memory devices such as a ROM or a RAM.
The control unit is connected via signal lines to the outdoor unit, the indoor unit 5, and other components that form the refrigeration cycle, as well as the refrigerant sensor unit 10. The control unit receives various signals via signal lines sent from each component of the air conditioning apparatus 1, and also sends signals from the control unit to each component of the air conditioning apparatus 1. In this way, the control unit controls the operation of each component of the air conditioning apparatus 1.
The control unit and each unit of the air conditioning device 1 may be connected wirelessly via a communication unit, not limited to being connected by wire such as a signal line.

The control unit is connected to an operation unit 7, which is configured by a remote control, an operation panel, etc., via a signal line. The operation unit 7 in this embodiment is attached to a wall surface 101 of the indoor space 100.
A display panel is provided on the operation unit 7. The operation state of the operation unit 7 and the operating state of the air conditioning apparatus 1 are displayed on the display panel.
The operation unit 7 can input temperature settings, etc. In other words, the operation unit 7 functions as an input unit.

In this embodiment, the refrigerant used in the air conditioning apparatus 1 including the indoor unit 5 is a mildly flammable or flammable refrigerant, such as a mixed refrigerant containing R410A or R32. Some of these refrigerants are mildly flammable and some are flammable. In the event of a leak of a mildly flammable or flammable refrigerant, it is necessary to suppress the amount of refrigerant leakage so that the refrigerant concentration in the indoor space 100 does not reach the lower flammability limit (LFL). In particular, it is desirable to suppress the amount of refrigerant leakage from the indoor unit 5 installed in the indoor space 100 or nearby.
Furthermore, these refrigerants used in the air conditioner 1 are gases with a higher specific gravity than air.

A refrigerant sensor unit 10 is disposed near the indoor unit 5. The refrigerant sensor unit 10 detects the concentration of refrigerant in the indoor space 100 and emits an alarm sound to alert people in the indoor space 100 of a refrigerant leak.
The refrigerant sensor unit 10 detects the concentration of the refrigerant in the indoor space 100 and transmits a detection signal to the control unit via a signal line. The refrigerant sensor unit 10 of this embodiment is connected to the control unit via the operation unit 7.
Furthermore, the refrigerant sensor unit 10 can transmit and receive signals via a signal line to and from a control center or other external device outside the air conditioning apparatus 1. For example, the refrigerant sensor unit 10 can detect the concentration of refrigerant in the indoor space 100 and transmit a detection signal to the control center via the signal line.

The refrigerant sensor unit 10 is attached to a wall surface 101 .
As described above, when the refrigerant used by the air conditioning apparatus 1 is a gas having a higher specific gravity than air, it is desirable to install the refrigerant sensor unit 10 in the lower part of the indoor space 100 .
The refrigerant sensor unit 10 of this embodiment is attached at a position about 30 cm above the floor surface 102 of the indoor space 100 .

The refrigerant sensor unit 10 is supplied with power from a commercial power source via a power outlet box 105 provided on the wall surface 101 .
Specifically, the refrigerant sensor unit 10 is attached to the front of the outlet box 105 from which the front panel has been removed, and is electrically connected to a power supply line routed to the outlet box 105. In this way, the refrigerant sensor unit 10 is driven.

FIG. 2 is a perspective view of the refrigerant sensor unit 10. As shown in FIG.
As shown in FIG. 2 , the refrigerant sensor unit 10 includes a housing 12. The housing 12 is formed in a flat rectangular parallelepiped shape with an internal space 13 ( FIG. 5 ). When the refrigerant sensor unit 10 is installed in the interior space 100, the housing 12 is attached to the wall surface 101 with the rear wall 20, which has the largest flat surface among the side surfaces, facing the wall surface 101. In this case, a first side wall 22 located on the opposite side of the rear wall 20 is positioned facing the interior space 100. In other words, the first side wall 22 is positioned on the front surface of the housing 12.

The refrigerant sensor unit 10 is attached to the wall surface 101 so that the longitudinal direction of the housing 12 is aligned horizontally. Hereinafter, the refrigerant sensor unit 10 attached in this manner will be referred to as being in a horizontally placed state.
When the refrigerant sensor unit 10 is placed horizontally, a pair of second side walls 26 located in the longitudinal direction of the housing 12 are positioned at positions that form the side surfaces, and one of a pair of third side walls 28 that the housing 12 has is positioned at a position that forms the bottom surface of the housing 12.

Alternatively, the refrigerant sensor unit 10 may be mounted on the wall surface 101 so that the direction perpendicular to the longitudinal direction of the housing 12 (the up-down direction in each drawing) is aligned horizontally. Hereinafter, the refrigerant sensor unit 10 mounted in this manner is referred to as being in a vertically placed state.
This allows the installation state of the refrigerant sensor unit 10 to be changed depending on the shape of the outlet box 105 and the state of the indoor space 100.

When the refrigerant sensor unit 10 is placed upright, a pair of third side walls 28 positioned perpendicular to the longitudinal direction of the housing 12 are positioned as side surfaces, and one of a pair of second side walls 26 of the housing 12 is positioned as the bottom surface of the housing 12.

A thin sheet member 14 is attached to approximately the center of the first side wall 22 of the housing 12. In this embodiment, the sheet member 14 is made of resin and has a thickness of approximately 0.2 mm. However, the sheet member 14 is not limited to this and may be made of any material and have any thickness as long as it can cause the refrigerant sensor unit 10 to emit a predetermined amount of alarm sound.
Two sound emission holes 40, which are through holes, are provided side by side in approximately the center of the sheet member 14.

FIG. 3 is a perspective view of the refrigerant sensor unit 10 with the sheet member 14 omitted.
2 and 3 , a pair of first openings 30, which are through-holes, are provided in the first side wall 22. These first openings 30 are provided so as to penetrate the first side wall 22 and the sheet member 14. That is, these first openings 30 communicate the internal space 13 of the housing 12 with the outside when the sheet member 14 is attached.
The pair of first openings 30 are arranged at a predetermined interval along the vertical direction of the housing 12. Furthermore, these first openings 30 are provided at a position close to one of the second side walls 26.

An insertion hole 32, which is a rectangular through-hole, is provided in the approximate center of the first side wall 22. This insertion hole 32 connects the internal space 13 of the housing 12 with the outside.
A recess 34 is provided in the first side wall 22 at a position adjacent to the insertion hole 32. This recess 34 has a groove shape that is recessed at a predetermined depth from the outer surface of the first side wall 22 toward the internal space 13 of the housing 12. One end of the recess 34 is connected to the insertion hole 32, and the recess 34 is formed to extend a predetermined length from the insertion hole 32 along the longitudinal direction of the first side wall 22.

The insertion hole 32 and the recess 34 are both covered by the sheet member 14 from the front side of the housing 12. That is, the first side wall 22 is provided with a hollow portion 36 formed by covering the recess 34 with the sheet member 14.
Furthermore, two sound emission holes 40 are arranged on the front side of the other end of the recess 34. Therefore, the internal space 13 of the housing 12 is connected to the outside of the housing 12 by the insertion hole 32, the hollow portion 36, and the sound emission holes 40.

FIG. 4 is a rear view of the refrigerant sensor unit 10.
A pair of second openings 31, which are through holes, are provided in one of the second side walls 26. These second openings 31 communicate the internal space 13 of the housing 12 with the outside.
The pair of second openings 31 are arranged at a predetermined interval along the vertical direction of the housing 12 .
More specifically, in this embodiment, the pair of second openings 31 are provided at corners of the housing 12 formed by one of the second side walls 26 and the rear wall 20 that forms the rear surface of the housing 12. That is, as shown in Figures 2 and 4, the pair of second openings 31 open toward one side surface and the rear surface of the housing 12 when the refrigerant sensor unit 10 is placed horizontally.
As described above, the second side wall 26 on one side of which the second openings 31 are provided has a pair of first openings 30 provided close to each other.

A wiring insertion hole 35 is provided in the approximate center of the rear wall 20, through which various wiring such as power supply lines and signal lines are inserted.
Additionally, a plurality of mounting holes 37 are provided in the rear wall 20. These mounting holes 37 are for mounting the housing 12 to the outlet box 105. The housing 12 is mounted to the outlet box 105 by fastening fastening members such as screws inserted into the mounting holes 37 to fastening portions such as screw holes of the outlet box 105.

These mounting holes 37 are all formed in an elongated hole shape to accommodate dimensional tolerances and the state of the arrangement position of the refrigerant sensor unit 10 .
In addition, the multiple mounting holes 37 are provided so that the refrigerant sensor unit 10 can be placed either vertically or horizontally.

Furthermore, the rear wall 20 is provided with a plurality of mounting holes 37 that are different in position and shape from one another in order to accommodate screw holes of different standards of the outlet boxes 105 .
For example, as shown in Fig. 4, each mounting hole 38 corresponds to a screw hole in the standard for outlet boxes 105 in Germany, France, Spain, etc. Also, each mounting hole 39 corresponds to a screw hole in the standard for outlet boxes 105 in Italy.
The mounting holes 37 shown in FIG. 4 are merely an example, and may be formed in any position and shape according to a predetermined standard.

Fig. 5 is a cross-sectional view taken along plane V in Fig. 2. Fig. 6 is a cross-sectional view taken along plane VI in Fig. 2. Note that the sheet member 14 is omitted in Fig. 6.
As shown in FIGS. 5 and 6, the housing 12 has an internal space 13 .

The internal space 13 is provided with ribs 21, 23 that stand up from the rear wall 20 and the first side wall 22. These ribs 21, 23 both extend in the vertical direction of the housing 12. The ends of these ribs 21, 23 abut against each other. Therefore, the internal space 13 is divided into two spaces along the longitudinal direction of the housing 12 by these ribs 21, 23.
Each of the ribs 21, 23 terminates at a predetermined width substantially at the center in the direction perpendicular to the longitudinal direction of the housing 12. This provides a rectangular communication opening 19 that connects the two spaces separated by the ribs 21, 23.

These ribs 21, 23 are both disposed at positions closer to one of the second side walls 26 than to the center in the longitudinal direction of the housing 12. Therefore, the internal space 13 is divided into two spaces, one large and one small, along the longitudinal direction of the housing 12 by these ribs 21, 23.
Hereinafter, the smaller space, i.e., the space located on one side of the second side wall 26, will be referred to as the sensor chamber 15. The larger space, i.e., the space located on the other side of the second side wall 26, will be referred to as the control chamber 17.

A control unit 18 is provided in the control room 17. The control unit 18 includes a flat circuit board 50 and various electronic components mounted on the circuit board 50.
The circuit board 50 is disposed in the control room 17 with its flat surface facing the rear wall 20 and the first side wall 22. In the present embodiment, the circuit board 50 is fixed to the first side wall 22 at a predetermined distance from the first side wall 22 by fastening members such as screws.

An insulating sheet 52 is provided on the surface of the circuit board 50 facing the rear wall 20. This prevents discharge to the circuit board 50 when a worker touches the circuit board 50 during maintenance work on the refrigerant sensor unit 10.
In addition, a terminal block 54 to which signal lines are connected, a CPU, etc. are provided on the surface of the circuit board 50 facing the rear wall 20 .

A buzzer device 56 is provided on the surface of the circuit board 50 facing the first side wall 22. The buzzer device 56 is an electronic component that emits an alarm sound. The buzzer device 56 has a flattened rectangular parallelepiped shape and is inserted into the insertion hole 32. The upper surface of the buzzer device 56 inserted into the insertion hole 32 is covered by the sheet member 14 when viewed from the front of the housing 12, and is positioned at a distance from the sheet member 14.

The sensor chamber 15 houses the detection unit 16. The detection unit 16 includes a refrigerant sensor 60, a sensor board 62 on which the refrigerant sensor 60 is mounted, and a connection terminal 64 extending from the sensor board 62.

The refrigerant sensor 60 is a sensor component that detects refrigerant. The refrigerant sensor 60 has a cylindrical shape and is mounted on the flat sensor substrate 62 so that its longitudinal axis extends upright from the top surface of the sensor substrate 62.

The sensor board 62 is disposed in the sensor chamber 15 with its flat surface facing the rear wall 20 and the first side wall 22. In the present embodiment, the circuit board 50 is fixed to the first side wall 22 at a predetermined distance from the first side wall 22 by engaging with a plurality of engaging ribs 25 that extend up from the first side wall 22. In this case, the end of the refrigerant sensor 60 that extends up from the sensor board 62 is disposed at a predetermined distance from the first side wall 22.
The connection terminal 64 extends from the end of the sensor board 62 toward the control chamber 17 and is connected to the circuit board 50 via the communication opening 19. In this way, the detection unit 16 is electrically connected to the control unit 18.

The pair of first openings 30 and the pair of second openings 31 described above are both provided in positions in the housing 12 corresponding to the sensor chamber 15. In other words, the pair of first openings 30 and the pair of second openings 31 connect the sensor chamber 15 to the outside of the housing 12.

The refrigerant sensor 60 and the sensor board 62 are disposed between the pair of first openings 30 in a direction perpendicular to the longitudinal direction of the housing 12 when viewed from the front of the housing 12. In other words, the refrigerant sensor 60 and the sensor board 62 are disposed in a position that does not face either of the pair of first openings 30.
Furthermore, the refrigerant sensor 60 and the sensor board 62 are disposed in approximately the same position as the pair of first openings 30 in the longitudinal direction of the housing 12 when viewed from the front of the housing 12. That is, the refrigerant sensor 60, the sensor board 62, and the pair of first openings 30 are disposed on the same line in a direction perpendicular to the longitudinal direction of the housing 12. Therefore, the refrigerant sensor 60 is disposed adjacent to the pair of first openings 30.

The refrigerant sensor 60 and the sensor board 62 are disposed between the pair of second openings 31 in a side view of the housing 12 in a direction perpendicular to the longitudinal direction of the housing 12. In other words, the refrigerant sensor 60 and the sensor board 62 are disposed in a position that does not face either of the pair of second openings 31.
Furthermore, as described above, the pair of second openings 31 are both provided at positions in the housing 12 corresponding to the sensor chamber 15 , and therefore the refrigerant sensor 60 is positioned adjacent to the pair of second openings 31 .

[1-2. Operation]
The operation of the refrigerant sensor unit 10 configured as above will now be described.
In the air conditioning apparatus 1, refrigerant may leak into the indoor space 100 via the indoor unit 5. In this embodiment, the refrigerant used in the air conditioning apparatus 1 is a gas with a higher specific gravity than air, and therefore, refrigerant that leaks into the indoor space 100 accumulates in the indoor space 100 and accumulates on the floor surface 102. If refrigerant continues to leak into the indoor space 100, the refrigerant that has accumulated on the floor surface 102 eventually flows into the sensor chamber 15 of the refrigerant sensor unit 10 via each of the first openings 30 and each of the second openings 31.

The refrigerant sensor 60 detects the concentration of refrigerant that has flowed into the sensor chamber 15. The refrigerant sensor unit 10 activates the buzzer device 56 when the refrigerant concentration detected by the refrigerant sensor 60 exceeds a predetermined value. When the buzzer device 56 is activated, an alarm sound is emitted, and the refrigerant sensor unit 10 thereby alerts people in the indoor space 100 of a refrigerant leak.

The refrigerant sensor unit 10 also detects the concentration of refrigerant in the indoor space 100 and transmits a detection signal to the control unit via a signal line. Upon receiving the detection signal, the control unit causes each part of the air conditioning unit 1 to perform operations related to refrigerant leakage prevention measures, such as displaying a specified message on the display panel of the operation unit 7 or causing the indoor unit 5 to perform fan operation. In this way, the air conditioning unit 1 attempts to suppress an increase in refrigerant concentration in the indoor space 100.

The control unit may receive a detection signal from the refrigerant sensor unit 10 and determine whether or not a refrigerant leak has occurred in the indoor space 100. Furthermore, the control unit may control the buzzer device 56.
The refrigerant sensor unit 10 may also determine whether or not a refrigerant leak has occurred in the indoor space 100. Furthermore, the refrigerant sensor unit 10 may be capable of causing a predetermined display to be displayed on the display panel of the operation unit 7, or causing the indoor unit 5 to perform an air blowing operation, etc.

As described above, in the refrigerant sensor unit 10 , the refrigerant sensor 60 and the sensor board 62 are disposed in positions that do not face either of the pair of first openings 30 and are adjacent to the pair of first openings 30 .
As a result, even if a person using the indoor space 100 brings a statically charged finger or other object close to the refrigerant sensor unit 10, static electricity is prevented from being discharged to the refrigerant sensor 60 and the sensor board 62 through the pair of first openings 30. Therefore, even when the refrigerant sensor unit 10 is placed in the indoor space 100, malfunction of the refrigerant sensor unit 10 is prevented.

Similarly, in the refrigerant sensor unit 10 , the refrigerant sensor 60 and the sensor board 62 are disposed in positions that do not face either of the pair of second openings 31 and are adjacent to the pair of second openings 31 .
This prevents static electricity from being discharged to the refrigerant sensor 60 and the sensor board 62 through the pair of second openings 31 .

As described above, the refrigerant sensor unit 10 is configured to be attachable to the wall surface 101 in an upright position. In this case, one of the second side walls 26 is positioned at the bottom surface of the housing 12. That is, the pair of second openings 31 are positioned at the bottom surface of the housing 12. This allows the refrigerant accumulating on the floor surface 102 to flow more quickly into the sensor chamber 15, enabling the refrigerant sensor 60 to more quickly detect a refrigerant leak.
Furthermore, since the pair of second openings 31 are arranged facing downward, dirt, dust, etc. are prevented from entering the internal space 13 through these second openings 31.

As described above, when the buzzer device 56 is driven, the alarm sound emitted by the buzzer device 56 travels through the hollow portion 36 and is emitted to the outside of the housing 12 from the two sound emission holes 40. In other words, the hollow portion 36 functions as a flow path for the alarm sound of the buzzer device 56.
Furthermore, because the recess 34 and the buzzer device 56 are covered by the thin sheet member 14, part of the alarm sound emitted by the buzzer device 56 passes through the sheet member 14 and is emitted to the outside of the housing 12. This allows the refrigerant sensor unit 10 to emit an alarm sound at a sufficient volume.

Furthermore, in the refrigerant sensor unit 10 , the buzzer device 56 is disposed at a position not facing either of the two sound emission holes 40 but adjacent to each of the sound emission holes 40 .
This prevents static electricity from being discharged to the buzzer device 56 through the two sound emission holes 40 .

The internal space 13 of the housing 12 is divided into a sensor chamber 15 and a control chamber 17 by ribs 21 and 23. This limits the space around the refrigerant sensor 60 to the sensor chamber 15, making it easier for the concentration of refrigerant flowing in through each first opening 30 and each second opening 31 to increase. Therefore, if refrigerant flows into the internal space 13, the refrigerant sensor 60 can quickly detect a refrigerant leak. In addition, if refrigerant flows into the internal space 13, contact of the refrigerant with the circuit board 50 is prevented.

[1-3. Effects, etc.]
As described above, in this embodiment, the refrigerant sensor unit 10 includes the housing 12 attached to the wall surface 101 of the indoor space 100, which is the space to be air-conditioned by the air conditioning apparatus 1, and the refrigerant sensor 60 housed inside the housing 12. The first side wall 22 forming one side of the housing 12 is provided with the first opening 30 that connects the inside and outside of the housing 12, and the first opening 30 is provided in a position adjacent to the refrigerant sensor 60 but does not face it.

This prevents static electricity from being discharged to the refrigerant sensor 60 and the sensor board 62 through the pair of first openings 30. Therefore, even when the refrigerant sensor unit 10 is placed in the indoor space 100, malfunction of the refrigerant sensor 60 is prevented.

Furthermore, according to this embodiment, a second opening 31 is provided in a second side wall 26 different from the first side wall 22. The second opening 31 is provided in a position adjacent to but not facing the refrigerant sensor 60, and the second side wall 26 may be disposed in a position that becomes the bottom surface or one side surface of the housing 12 when the housing 12 is attached to the wall surface 101.
This allows the installation state of the refrigerant sensor unit 10 to be changed depending on the shape of the outlet box 105 and the state of the indoor space 100. Therefore, the refrigerant sensor unit 10 can be installed in a wider variety of installation states and can be installed to more reliably detect refrigerant leaks.

Furthermore, according to this embodiment, the housing 12 is provided with a buzzer device 56 that emits an alarm sound, and the housing 12 is provided with a sound emission hole 40 that connects the inside and outside of the housing 12 and emits the alarm sound to the outside of the housing 12, and the sound emission hole 40 may be provided in a position adjacent to the buzzer device 56 but not facing it.
This prevents static electricity from being discharged to the buzzer device 56 through the two sound emission holes 40. Therefore, even when the refrigerant sensor unit 10 is placed in the indoor space 100, malfunction of the buzzer device 56 is prevented.

Furthermore, according to this embodiment, the housing 12 may be provided with a cavity 36 that connects the buzzer device 56 to the sound emission hole 40 and through which the notification sound flows.
As a result, the buzzer device 56 is provided adjacent to but not facing the sound emission holes 40. Therefore, static electricity is prevented from being discharged to the buzzer device 56 via the two sound emission holes 40.

Furthermore, according to this embodiment, a thin sheet member 14 is attached to the first side wall 22 of the housing 12, and a recess 34 is provided in the first side wall 22. The recess 34 may be disposed at a position adjacent to the buzzer device 56, and the hollow portion 36 may be formed by the recess 34 and the sheet member 14 covering the recess 34.
As a result, part of the alarm sound emitted by the buzzer device 56 passes through the sheet member 14 and is emitted to the outside of the housing 12. This allows the refrigerant sensor unit 10 to emit an alarm sound at a sufficient volume.

(Other embodiments)
As described above, the above-described embodiments have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to these, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. Furthermore, it is also possible to combine the components described in the above-described embodiments to create new embodiments.
Therefore, other embodiments will be exemplified below.

In the above embodiment, the pair of first openings 30 and the pair of second openings 31 are provided in each of the first side wall 22 and one of the second side walls 26 .
However, the present invention is not limited to this, and the third opening may be provided in one of the third side walls 28 .

The third opening connects the sensor chamber 15 to the outside of the housing 12. The third opening is provided adjacent to the refrigerant sensor 60 but does not face it.
This prevents static electricity from being discharged to the refrigerant sensor 60 and the sensor board 62 through the third opening. Therefore, even when the refrigerant sensor unit 10 is placed in the indoor space 100, malfunction of the refrigerant sensor 60 is prevented.

The third side wall 28 on which the third opening is provided is located on the bottom surface when the refrigerant sensor unit 10 is placed horizontally. This allows refrigerant accumulating on the floor surface 102 to flow more quickly into the sensor chamber 15, allowing the refrigerant sensor 60 to detect refrigerant leaks more quickly and preventing dirt, dust, and the like from entering the internal space 13 through the third opening.
Furthermore, the third side wall 28 on which the third opening is provided is located on the side surface when the refrigerant sensor unit 10 is placed upright.

In the above embodiment, the refrigerant sensor 60 and the sensor board 62 are located close to one of the second side walls 26 and at approximately the center of the housing 12 in the direction perpendicular to the longitudinal direction of the housing 12 .
However, without being limited to this, the refrigerant sensor 60 and the sensor board 62 may be positioned close to one of the second side walls 26 and close to one of the third side walls 28 in a direction perpendicular to the longitudinal direction of the housing 12.

As a result, when the refrigerant sensor unit 10, which is provided with the third opening, is placed horizontally, the refrigerant accumulating on the floor surface 102 flows more quickly into the sensor chamber 15, allowing the refrigerant sensor 60 to more quickly detect refrigerant leaks.

In the above-described embodiment, the buzzer device 56 is exposed to the outside of the housing 12 through the insertion hole 32 and is covered by the sheet member 14. However, this is not limited to this, and the entire device may be covered by the housing 12. In this case, a sound emission hole is provided in the housing 12 at a position adjacent to, but not facing, the buzzer device 56.

Note that the above-described embodiments are intended to illustrate the technology disclosed herein, and various modifications, substitutions, additions, omissions, etc. may be made within the scope of the claims or their equivalents.

This disclosure is applicable to refrigerant sensor units installed in the conditioned space of an air conditioner. Specifically, this disclosure is applicable to refrigerant sensor units that are provided outside the indoor unit of an air conditioner and attached to the indoor space that the air conditioner conditions.

REFRIGERATION NUMERALS 1 Air conditioning apparatus 10 Refrigerant sensor unit 12 Housing 13 Internal space 14 Sheet member 22 First side wall 26 Second side wall 28 Third side wall 30 First opening 31 Second opening 34 Recessed portion 36 Cavity 40 Sound emission hole 56 Buzzer device 60 Refrigerant sensor 100 Indoor space 101 Wall surface 102 Floor surface

Claims (7)

The air conditioning system includes a housing attached to a wall surface of an indoor space that is a conditioned space of the air conditioning system, and a refrigerant sensor housed inside the housing,
a first side wall forming one side surface of the housing is provided with a first opening that allows the inside and outside of the housing to communicate with each other;
a second side wall of the housing that is different from the first side wall is provided with a second opening that communicates the inside and the outside of the housing;
the first opening and the second opening are provided adjacent to the refrigerant sensor but not facing each other;
The second side wall is disposed at a position that becomes a bottom surface or one side surface of the housing when the housing is attached to the wall surface.
A refrigerant sensor unit characterized by: a third side wall different from the first side wall and the second side wall is provided with a third opening;
the third opening is provided at a position adjacent to the refrigerant sensor but not facing the refrigerant sensor,
The refrigerant sensor unit according to claim 1 , wherein the third side wall is disposed at a position that becomes a bottom surface or one side surface of the housing. the housing is formed so that at least one of the second side wall and the third side wall can be disposed on a bottom surface when the housing is attached to the wall surface;
The refrigerant sensor unit according to claim 2 , wherein the refrigerant sensor is disposed in a position close to at least one of the second side wall and the third side wall. the housing is formed so that both the second side wall and the third side wall can be disposed on a bottom surface when the housing is attached to the wall surface;
The refrigerant sensor unit according to claim 2 , wherein the refrigerant sensor is disposed in a position close to at least one of the second side wall and the third side wall. The housing is provided with a buzzer device that emits an alarm sound,
The housing has a sound emission hole that communicates the inside and outside of the housing and emits the notification sound to the outside of the housing.
The refrigerant sensor unit according to any one of claims 1 to 4 , wherein the sound emission hole is provided adjacent to the buzzer device but not facing the buzzer device. The refrigerant sensor unit according to claim 5 , wherein the housing is provided with a cavity that connects the buzzer device to the sound emission hole and through which the notification sound flows. a thin sheet member attached to one side of the housing;
A recess is provided on the one side surface,
the recess is disposed adjacent to the buzzer device,
The refrigerant sensor unit according to claim 6 , wherein the cavity is formed by the recess and the sheet member covering the recess.