AIR CONDITIONING UNIT AND AIR CONDITIONING SYSTEM

Abstract

The present invention relates to signaling a refrigerant leak. An air conditioning unit 1 comprises a variable part (17) whose visual appearance changes upon contact with a flammable refrigerant, an image capture means (12) that captures images of the variable part (17), and a detection means (101) that detects a refrigerant leak in the event of a change in the image of the variable part (17) captured by the image capture means (12). Figure for the abstract: Fig. 3

Description

Title of the invention: AIR CONDITIONING APPLIANCE AND AIR CONDITIONING SYSTEM technical field

[0001] The present invention relates to an air conditioning device and an air conditioning system. Previous techniques

[0002] HFC refrigerants used in air conditioning units have a high global warming potential (GWP), and their phase-out is planned to combat climate change. Propane, a refrigerant with a low GWP and high efficiency, is considered one of the next-generation refrigerants. However, it poses a safety problem due to its flammability in the event of a leak inside the unit. Regarding refrigerant leaks, document JP 2002-195707 A describes a refrigeration cycle device comprising a refrigerant detection element that changes color upon contact with the refrigerant to visibly detect any refrigerant leak in the refrigeration cycle device that uses a flammable refrigerant.

[0003] However, since the air conditioning unit is often installed in a location far from the user, even if a refrigerant detection device is installed on the unit, it is not always visible to the user, hence the problem of the difficulty in detecting refrigerant leaks. Description of the invention

[0004] To solve this problem, the present invention aims to detect a refrigerant leak.

[0005] The present invention provides an air conditioning device comprising a variable part whose visual appearance changes upon contact with a flammable refrigerant, an image capture means which captures images of said variable part and a detection means which detects a refrigerant leak in the event of a change in the image of said variable part captured by said image capture means.

[0006] Advantageously, said image capture means is placed on the front face of an indoor unit and

[0007] said variable part is placed opposite said image capture means.

[0008] Optionally, said variable part is placed inside a top-bottom blower flap provided in said indoor unit.

[0009] Advantageously, said variable part is placed between the front face of said indoor unit and a filter.

[0010] Optionally, the air conditioning unit further includes an air flow regulator which ensures, in the event of detection of a refrigerant leak by said detection means, ventilation at a flow rate above a threshold.

[0011] Advantageously, said image capture means further captures images of an air-conditioned space and

[0012] said airflow regulator ensures the adjustment of the direction of the airflow according to the situation of said air-conditioned space captured by said image capture means.

[0013] Optionally, the air conditioning unit further includes an output processor which, in the event of detection of a refrigerant leak by said detection means, requests an output means to output leak detection information.

[0014] According to one embodiment, said image capture means captures images of the air-conditioned space,

[0015] said output processor requests, in the event of detection of a refrigerant leak by said detection means, an audible broadcasting means to output said leak detection information if a human presence is detected in the image of said air-conditioned space captured by said image capture means, or transmits said leak detection information to a predetermined recipient if no human presence is detected.

[0016] Advantageously, the air conditioning unit further includes a thermal camera and wherein said output processor outputs the alert information in the event of detection by said thermal camera of a temperature equal to or greater than a predetermined threshold in the air-conditioned space.

[0017] The present invention provides an air conditioning system comprising a variable part whose visual appearance changes upon contact with a flammable refrigerant, an image capture means which captures images of said variable part and a detection means which detects a refrigerant leak in the event of a change in the image of said variable part captured by said image capture means.

[0018] The present invention makes it possible to detect refrigerant leaks. Brief description of the drawings

[0019] Other objects, features and advantages of the invention will become apparent from the following description, given solely by way of non-limiting example and made with reference to the accompanying drawings in which:

[0020] - Fig. 1 represents an external configuration of an air conditioning unit;

[0021] - Fig. 2 represents a refrigerant circuit;

[0022] - The [Fig.3] represents a structure of an internal unit;

[0023] - Figure 4A is an enlarged view of an image capture means and part variable;

[0024] - Figure 4B is an enlarged view of the image capture means and part variable;

[0025] - The [Fig.5A] represents the variable part;

[0026] - The [Fig.5B] represents the variable part;

[0027] - The [Fig.6] represents a configuration of the indoor unit;

[0028] - Figure 7 is a diagram illustrating the leak detection process of refrigerant;

[0029] - Figure 8 represents a variant of the arrangement of the variable part; and

[0030] - Fig. 9 represents a variant of the arrangement of the variable part. Detailed description

[0031] Figure 1 shows an external configuration of an air conditioning unit 1 according to one embodiment. The air conditioning unit 1 conditions the air by circulating a refrigerant in a refrigeration cycle (heat pump cycle). As shown in Figure 1, the air conditioning unit 1 comprises an indoor unit 10 installed inside the room (air-conditioned space), an outdoor unit 20 installed outside (outside the room), and a remote control 30 operated by the user.

[0032] The indoor unit 10 includes a remote communication means 11. The remote communication means 11 receives a signal emitted by the remote control 30, in particular via infrared communication. Furthermore, the remote communication means 11 transmits a predetermined signal to the remote control 30. The remote communication means 11 receives from the remote control 30, in particular, the start / stop control signals, temperature change signals, operating mode change signals, and timer setting signals. The indoor unit 10 and the outdoor unit 20 are connected by a refrigerant line and a communication cable (not shown in [Fig. 1]). The indoor unit 10 further includes an image capture means 12. The image capture means 12 captures images of the conditioned space, in particular using a CMOS (complementary metal oxide semiconductor) image sensor.The image capture means 12 is placed, as shown in [Fig. 1], at the bottom of a front face 161 of the indoor unit 10 and approximately at the center in the lateral direction.

[0033] Figure 2 shows a refrigerant circuit Q in the air conditioning unit 1 according to the embodiment. The solid arrows in Figure 2 show the refrigerant flow in heating mode, and the dashed arrows in Figure 2 show the refrigerant flow in cooling mode. A low GWP refrigerant such as propane is used.

[0034] The indoor unit 10 comprises, in addition to the remote communication means 11 and the image capture means 12, an indoor heat exchanger 14 and an indoor fan 15. In the indoor heat exchanger 14, heat exchange takes place between the refrigerant circulating in the heat transfer tube and the indoor air drawn in by the indoor fan 15. The indoor heat exchanger 14 functions as a condenser or an evaporator by switching a four-way valve 25 described below. The indoor fan 15 is installed near the indoor heat exchanger 14. The indoor fan 15 forces the indoor air into the indoor heat exchanger 14.

[0035] The outdoor unit 20 comprises a compressor 21, an outdoor heat exchanger 22, an outdoor fan 23, an expansion valve 24, and a four-way valve 25. The compressor 21 compresses a gaseous refrigerant at low temperature and low pressure and discharges a gaseous refrigerant at high temperature and high pressure. In the outdoor heat exchanger 22, heat exchange occurs between the refrigerant circulating in the heat transfer tube and the outside air drawn in by the outdoor fan 23. The outdoor heat exchanger 22 functions as either a condenser or an evaporator through the switching of the four-way valve 25.

[0036] As shown in [Fig. 1], the outdoor fan 23 is installed near the outdoor heat exchanger 22. The outdoor fan 23 blows outside air into the outdoor heat exchanger 22. The expansion valve 24 is used to decompress the refrigerant condensed by the condenser (the one located between the outdoor heat exchanger 22 and the indoor heat exchanger 14). The refrigerant decompressed by the expansion valve 24 is then directed to the evaporator (the one located between the outdoor heat exchanger 22 and the indoor heat exchanger 14). The four-way valve 25 is a switching valve for the refrigerant circulation path, depending on the operating mode of the air conditioning unit 1.

[0037] Fig. 3 represents a structure of the inner unit 10. Fig. 3 is a sectional view perpendicular to the rear face 18 of the inner unit 10 and parallel to the top-to-bottom direction of the inner unit 10. In the following description, the direction of the x-axis in 3D coordinates as shown in Fig. 3 (towards the bottom of the page) corresponds to the lateral direction of the inner unit 10, the direction of the y-axis (longitudinal direction of the page) corresponds to the top-to-bottom direction of the inner unit 10 (the top of the page corresponds to the upper side) and the direction of the z-axis (lateral direction of the page) corresponds to the depth direction of the inner unit 10. In the lateral direction, the right corresponds to the right side seen in the depth direction (towards the front of the page) and the left corresponds to the left side seen in the depth direction (towards the bottom of the page).

[0038] The indoor unit 10 is installed near the ceiling of the room so that its rear face 18 is in contact with a wall B. In [Fig. 3], the room, namely the space air-conditioned, extends along the left side of the page and the indoor unit 10 has a structure allowing ventilation in order to regulate the room temperature.

[0039] The indoor unit 10 comprises the indoor fan 15 within an enclosure 16 having a front face 161 with an air inlet port and a top face 162. The indoor heat exchanger 14 is located in a space delimited by the front face 161, the top face 162 and the indoor fan 15. In the indoor heat exchanger 14, heat exchange takes place with an airflow generated by the activation of the indoor fan 15. The indoor unit 10 is further provided with a front filter 141a provided on the front face 161, a top filter 141b provided on the top face 162, an up-down air outlet 142 and a housing 143.

[0040] Air is drawn in through the front panel 161 and the top panel 162 into the indoor unit 10 and, after the removal of large dust particles by means of the front filter 141a and the top filter 141b, passes through the indoor heat exchanger 14. Activation of the indoor fan 15 creates an airflow through the indoor heat exchanger 14. The indoor fan 15 may be, in particular, a tangential fan. However, it is sufficient that the indoor fan 15 be capable of creating an airflow and is not limited to tangential fans. The air having passed through the indoor heat exchanger 14 is guided by the indoor fan 15 to the casing 143 and then ejected into the conditioned space, the direction of the airflow being regulated by the up-down supply flap 142 and a left-right supply flap (not shown).

[0041] Furthermore, the image capture means 12 is located at the bottom of the front face 161. The variable part 17 is provided between the image capture means 12 and the front face 161. The variable part 17 is a lamellar element bonded to the top-to-bottom blower flap 142, notably by means of double-sided tape. The variable part 17 changes its pattern by reacting with the refrigerant.

[0042] Figures 4A and 4B are enlarged views of the image capture means 12 and the variable part 17. The image capture means 12 can rotate 360 ​​degrees laterally (about the xz plane). The image capture means 12 can also rotate up and down (about the y-axis). In addition, the variable part 17 can rotate laterally from the position where it does not overlap the image capture means 12, as shown in [Fig. 4A], to the position where it overlaps the image capture means 12, as shown in [Fig. 4B]. In the position where it overlaps the image capture means 12, the variable part 17 is positioned opposite the image capture means 12. Thus, the variable part 17 enters the field of view (image capture field) of the image capture means 12, and an image of the variable part 17 can be obtained. The image capture means 12 periodically captures images.The image capture method 12 captures. Images are captured using the backup power supply, even when the air conditioning is not activated. Furthermore, the image capture device 12 captures the image of the variable part 17 at regular intervals. For example, the image capture device 12 captures the image of the air-conditioned space at a first interval and the image of the variable part 17 at a second interval. In this case, the second interval is longer than the first. The variable part 17 moves at the second interval to the position where it overlaps with the image capture device 12.

[0043] Figures 5A and 5B represent the variable part 17. Figure 5A represents the variable part 17 in the absence of a refrigerant leak. Figure 5B represents the variable part 17 in the presence of a refrigerant leak. As described previously, propane is used as the refrigerant, and a foil impregnated with a substance that changes color upon contact with such a flammable refrigerant gas is placed as the variable part 17. Among the substances that change color upon contact with the refrigerant gas are precious metal compounds. In particular, platinum group metal compounds, and especially palladium oxide, exhibit a pronounced color change. Platinum group metals generally have a high standard electrode potential, and their compounds, such as chloride, nitrate, sulfate, oxide, etc., also exhibit a high standard electrode potential.These are easily transformed into monometal by the reduction reaction upon contact with a flammable gas such as hydrogen. In the present embodiment, palladium oxide is used. When the coolant leaks and comes into contact with the variable part 17, the area of ​​the variable part 17 impregnated with a precious metal compound changes color and, as shown in [Fig. 5B], the appearance of the variable part 17 changes, for example, from a monochrome appearance to a striped pattern. In the examples in Figures 5A and 5B, an area of ​​the variable part 17 is impregnated with a precious metal compound to obtain a striped pattern as shown in [Fig. 5B].

[0044] In another example, it is possible to form the variable part 17 by applying a mixture of a coating with a precious metal compound to the area to be occupied by the variable part 17. In another example, it is also possible to create the variable part 17 by mixing a precious metal compound into the plastic material.

[0045] Thus, in the event of a refrigerant leak, the pattern of the variable part 17 changes. However, the user may have difficulty noticing the change in the variable part 17 because the indoor unit 10 of the air conditioning unit 1 is often installed high up in the room. Therefore, the image capture means 12 of this embodiment captures the image of this variable part 17 to detect a refrigerant leak based on the captured image.

[0046] Figure 6 is a functional diagram of a configuration of the indoor unit 10 for refrigerant leak detection. The indoor unit 10 comprises a control unit 100, a communication means 110, a recording medium 120, a loudspeaker 130, and an image capture means 12. The control unit 100 includes a central processing unit, RAM, ROM, etc. (not shown), and ensures the execution of programs contained in the recording medium 120 and in the ROM. The communication means 110 is a device for communicating with an external device via a network. The control unit 100 ensures communication, in particular, with a user's portable terminal via the communication means 110. The recording medium 120 stores various information and programs. The loudspeaker 130 emits sound. The loudspeaker 130 is an example of a sound emitting means.

[0047] The control unit 100 functions as a detection means 101, a situation identification means 102, an airflow regulator 103, and an output processor 104, executing the programs contained in the storage medium 120 and in read-only memory. In other words, in the following description, the process described as executed by the detection means 101, the situation identification means 102, the airflow regulator 103, and the output processor 104 is a process executed by the control unit 100.

[0048] The detection means 101 detects a refrigerant leak based on the image of the variable part 17 captured by the image capture means 12 (hereinafter referred to as the "image of the variable part"). The detection means 101 determines that a refrigerant leak has occurred when a captured image of the variable part differs from the one previously captured. Specifically, the detection means 101 determines that the two images are different when the degree of correspondence obtained by comparison with the previously captured image of the variable part is less than a certain threshold. In another example, the detection means 101 can determine that the two images are different when the number of pixels whose value has changed exceeds a certain threshold. Thus, the actual process for determining that the image of the variable part differs from the one previously captured is not limited to this embodiment.

[0049] The situation identification means 102 identifies the situation of the air-conditioned space based on the image of the air-conditioned space (hereinafter referred to as the "space image") captured by the image capture means 12. In particular, the situation identification means 102 identifies the size and position of objects such as furniture or a person located in the air-conditioned space. The airflow regulator 103 ensures the adjustment of the airflow rate and direction according to the situation of the air-conditioned space. The output processor 104 ensures, in the event of a refrigerant leak, the execution of a process to request an outlet. A leak detection signal indicating the detection of a leak. The output means that outputs the leak detection information is the loudspeaker 130 and the communication means 110.

[0050] Figure 7 is a diagram illustrating the refrigerant leak detection process performed by the control unit 100 of the indoor unit 10. According to the refrigerant leak detection process, the control unit 100 first requests the image capture means 12 to S100 to begin image capture. Then, the detection means 101 detects a possible refrigerant leak at S102 based on the image of the variable part obtained periodically. As described previously, the detection means 101 judges that a refrigerant leak is occurring if the image of the variable part changes. Then, the situation identification means 102 identifies the situation of the conditioned space at S104 based on the image of the space captured by the image capture means 12.

[0051] Next, the airflow regulator 103 ensures that S106 adjusts the airflow rate and direction according to the situation of the conditioned space identified by S104. In particular, the airflow regulator 103 sets the direction of the airflow towards an area unoccupied by objects and people. Furthermore, the airflow regulator 103 sets the airflow rate to a level equal to or greater than the predetermined threshold. For example, when the airflow rate can be set to three levels, namely low, medium, and high, the airflow regulator 103 sets the airflow rate to a high level. Thus, the leaking refrigerant flows at a relatively high rate towards the area unoccupied by objects and people. Consequently, the leaking refrigerant will be rapidly dispersed, and the refrigerant concentration in the conditioned space may be equal to or less than a level likely to cause combustion.Furthermore, any leakage of the refrigerant towards humans can perhaps be avoided.

[0052] Next, the output processor 104 checks S108, based on the image of the space captured by the image capture device 12, whether or not there is a person or persons in the air-conditioned space. If a human presence is detected (Y at S108), the output processor 104 broadcasts the leak detection audible message (S110) via the loudspeaker 130. For example, the loudspeaker 130 broadcasts the following leak detection audible message: "Refrigerant is leaking. Ensure ventilation."

[0053] If no human presence is detected (N to S108), the output processor 104 transmits the leak detection information via the communication means 110 to a predetermined recipient (S112). In this case, the predetermined recipient is, in particular, a handheld terminal belonging to the user of the air conditioning unit 1. Thus, any refrigerant leak can be reported to the user. Furthermore, the recipient can be changed depending on whether or not the user is present in the air-conditioned space. Thus, any refrigerant leak can be reliably reported to the user.

[0054] It should be noted that the present invention is not limited to such a specific embodiment and several variants and modifications can be envisaged within the limits of the essential elements of the present invention as set out in the claims, for example the application of a variant of one embodiment to another embodiment.

[0055] According to a first embodiment, the indoor unit 10 may further include a thermal imaging camera. The thermal imaging camera is located on the front face 161 of the indoor unit 10 and captures a thermal image showing the temperature distribution in the conditioned space by detecting the infrared radiation emitted by each object. Thus, it is possible to trigger an alert if a temperature equal to or exceeding a predetermined threshold is detected, for example, for the stove. This can prevent the ignition of a leaking refrigerant. In this case, the temperature threshold can be determined based on the refrigerant's combustion temperature.

[0056] According to a second embodiment, the image capture means 12 can capture the image comprising both the climate-controlled space and the variable part 17. For example, the variable part 17 can be positioned to occupy a portion of the image capture field, in particular the lower right portion. Thus, the image of the variable part 17 can be captured along with the climate-controlled space without moving the variable part 17.

[0057] According to a third embodiment, the position of the variable part 17 is not limited to that of the embodiment. It is sufficient for the variable part 17 to be positioned opposite the image capture means 12, in particular within the image capture field covered by the image capture means 12. For example, as shown in [Fig. 8], the variable part 17 can be positioned inside the up-down air vent 142. In another example, as shown in [Fig. 9], the variable part 17 can be positioned between the image capture means 12 and the internal heat exchanger 14, in particular on the front filter 141a. In this case, the image capture means 12 must be able to pivot to capture the image of the variable part 17 positioned on the front filter 141a. Thus, the variable part 17 is preferably positioned at the bottom of the indoor unit 10.This position allows it to detect refrigerant leaks flowing from the top because refrigerant is heavier than air.

[0058] According to a fourth embodiment, it is sufficient that the airflow regulator 103 be able to adjust the direction of the air according to the situation in the air-conditioned space, and its specific process is not limited to that of the embodiment. For example, the airflow regulator 103 can adjust the airflow rate so that it increases as the number of objects detected in the air-conditioned space increases.

[0059] According to a fifth variant, the airflow regulator 103 can adjust the direction of the air downwards for a certain time after the detection of the refrigerant leak, Regardless of the situation in the air-conditioned space, the refrigerant is then directed upwards to disperse any leaking refrigerant throughout the entire space. Because it is heavier than air, the refrigerant may initially stagnate just below the indoor unit 10. This variation allows for the rapid dispersion of any leaking refrigerant that may be stagnating just below the indoor unit 10.

[0060] According to a sixth embodiment, the output processor 104 can vary the output information depending on the situation of the climate-controlled space. For example, the output processor 104 can, when a window is detected in the image of the space captured by the image capture means 12, output via the speaker 130 information that prompts an action such as: "Open the window".

[0061] According to a seventh embodiment, the recipient of the leak detection information can be either the speaker 130 only, or the recipient's handheld terminal only. In another example, the leak detection information can be displayed on a display area provided on the remote control, for example, to replace or supplement the speaker 130 and the recipient's handheld terminal.

[0062] According to an eighth variant, the position of each function of the control unit 100 (detection means 101, situation identification means 102, airflow regulator 103, and output processor 104 of the indoor unit 10), the loudspeaker 130, the image capture means 12, and the variable portion 17 of this embodiment shown in [Fig. 6] is not limited to that of the embodiment. For example, if the air conditioning unit 1 is controlled by the central unit (not shown) provided independently of said air conditioning unit, this central unit can be equipped with all the functions of the control unit 100. Furthermore, it is sufficient for the loudspeaker 130 to be installed in the air-conditioned space and it is not necessarily integrated into the indoor unit 10. The variable portion 17 can be provided independently of the indoor unit 10.It should be noted that the variable part 17 must be placed in a position that is both exposed to the flow of leaking refrigerant and within the field of view of the image capture means 12, for example on the wall just below the indoor unit 10. It is sufficient that the image capture means 12 be placed in a position where it can capture the image of the conditioned space and that of the variable part 17 and it is not necessarily integrated into the indoor unit 10.

[0063] According to another variant, the variable part 17 and the image capture means 12 can be provided in the outdoor unit 20. In this case, the refrigerant leaking from the side of the outdoor unit 20 can be detected.

[0064] According to a ninth variant, it is sufficient that the variable part is that which changes its visual appearance upon contact with the flammable refrigerant and, for example, that which changes its color. List of reference signs

[0065] 1 Air conditioning unit

[0066] 10 Indoor Unit

[0067] 11 Means of remote communication

[0068] 12 Image capture means

[0069] 14 Internal heat exchanger

[0070] 15 Indoor fan

[0071] 16 Enclosure

[0072] 17 Variable part

[0073] 18 Rear view

[0074] 20 Outdoor Unit

[0075] 21 Compressor

[0076] 22 Outdoor heat exchanger

[0077] 23 Outdoor fan

[0078] 24 Regulator

[0079] 25 Four-way valve

[0080] 100 Control Unit

[0081] 101 Detection Means

[0082] 102 Means of identifying situations

[0083] 103 Airflow regulator

[0084] 104 Output Processor

[0085] 110 Means of communication

[0086] 120 Recording medium

[0087] 130 Speaker

[0088] 141a Front filter

[0089] 141b Upper Filter

[0090] 142 Up-down blower flap

[0091] 143 Housing

[0092] 161 Front view

[0093] 162 Upper face

Claims

Demands

1. Air conditioning apparatus (1) characterized in that it comprises: - a variable part (17) whose color changes upon contact with a flammable refrigerant, - an image capture means (12) which captures images of said variable part (17) and - a detection means (101) which detects a refrigerant leak in the event of a change in the image of said variable part (17) captured by said image capture means (12).

2. Air conditioning apparatus (1) according to claim 1, wherein said image capture means (12) is placed on the front face (161) of an indoor unit (10) and said variable part (17) is placed opposite said image capture means (12).

3. Air conditioning unit (1) according to claim 2, wherein said variable part (17) is placed inside an up-down blower flap (142) provided in said indoor unit (10).

4. Air conditioning unit (1) according to claim 2, wherein said variable part (17) is placed between the front face (161) of said indoor unit (10) and a filter.

5. Air conditioning unit (1) according to claim 1, further comprising an air flow regulator (103) which ensures, in the event of detection of a refrigerant leak by said detection means (101), ventilation at a flow rate above a threshold.

6. Air conditioning apparatus (1) according to claim 5, wherein said image capture means (12) further captures images of an air-conditioned space and said air flow regulator (103) ensures the adjustment of the direction of the air flow according to the situation of said air-conditioned space captured by said image capture means (12).

7. Air conditioning unit (1) according to claim 1, further comprising an output processor (104) which requests, in the event of detection of a refrigerant leak by said detection means (101), an output means to output leak detection information.

8. Air conditioning unit (1) according to claim 7, wherein said image capture means (12) captures images of the air-conditioned space, said output processor (104) requests, in the event of detection of a refrigerant leak by said detection means (101), an audio broadcasting means to output said leak detection information if a human presence is detected in the image of said air-conditioned space captured by said image capture means (12), or transmits said leak detection information to a predetermined recipient if no human presence is detected.

9. Air conditioning device (1) according to claim 7, further comprising a thermal camera and wherein said output processor outputs the alert information in the event of detection by said thermal camera of a temperature equal to or greater than a predetermined threshold in the air-conditioned space.

Images