Indoor unit control device, indoor unit provided with same, indoor unit control method, and indoor unit control program

Abstract

The present invention suppresses the accumulation of a refrigerant in a specific area by securing a desired air volume, the refrigerant being leaked under an air conditioning environment. An indoor unit control device (200) is provided with: a filter that is provided on a ventilation path and collects dust contained in a fluid passing through the ventilation path; and a cleaning mechanism that cleans the filter. The control device is provided with: a leakage detection unit (210) that is provided inside a housing of the indoor unit and that detects the amount of a refrigerant leakage; and a control unit (211) that, when the leakage is detected, executes a cleaning operation for cleaning the filter by the cleaning mechanism.

Description

Indoor unit control device, indoor unit equipped with the same, indoor unit control method, and indoor unit control program

[0001] The present disclosure relates to a control device for an indoor unit, an indoor unit equipped with the same, a control method for an indoor unit, and a control program for an indoor unit.

[0002] To mitigate global warming, there is a need to switch to refrigerants with low GWPs for air conditioners. However, when flammable refrigerants such as conventional hydrocarbons are used as low-GWP refrigerants, safety measures must be taken to prevent explosions and fires. Furthermore, when a leak detection sensor detects a flammable refrigerant leaking from an indoor unit, a safety measure is available that turns on the indoor unit fan to agitate the refrigerant and keep it below an ignition concentration. International standards also specify a minimum agitation airflow rate.

[0003] Patent Document 1 discloses that when a refrigerant detection unit such as a refrigerant sensor provided in an indoor unit detects a refrigerant leak, the air outlet opening and closing mechanism closes a portion of the air outlet to suppress or block the blowing of conditioned air from that portion during diffusion operation to diffuse the leaked refrigerant. By closing a portion of the air outlet in this way, the wind speed of the conditioned air blown out from the air outlet is increased, thereby improving the diffusion efficiency of the leaked refrigerant.

[0004] Patent No. 6222252

[0005] As mentioned above, a certain amount of airflow is required to agitate flammable refrigerant that has leaked from the indoor unit. However, in an actual air-conditioning environment, continued operation of the indoor unit can cause dust and other particles to clog the filter, potentially reducing the airflow. For this reason, it is desirable for the filter to be unclogged when the refrigerant sensor detects a refrigerant leak.

[0006] The present disclosure has been made in consideration of the above circumstances, and aims to provide an indoor unit control device that can prevent leaked refrigerant from accumulating in a specific area by ensuring a desired air volume, an indoor unit equipped with the same, a control method for the indoor unit, and a control program for the indoor unit.

[0007] A control device for an indoor unit according to one aspect of the present disclosure is a control device for an indoor unit that is provided on an air duct and includes a filter that captures dust contained in a fluid passing through the air duct and a cleaning mechanism that cleans the filter, and that is provided within the housing of the indoor unit and includes a leak detection unit that detects refrigerant leaks, and a control unit that, when the leak is detected, executes a cleaning operation to clean the filter using the cleaning mechanism.

[0008] An indoor unit according to one aspect of the present disclosure includes the indoor unit control device, the filter, and the cleaning mechanism.

[0009] A control method for an indoor unit according to one aspect of the present disclosure is a control method for an indoor unit that is provided on an air duct and has a filter that captures dust contained in a fluid passing through the air duct and a cleaning mechanism that cleans the filter, and includes a leakage detection step that detects the amount of refrigerant leakage within a housing of the indoor unit, and a control step that, when the leakage is detected, executes a cleaning operation using the cleaning mechanism to clean the filter.

[0010] A control program for an indoor unit according to one aspect of the present disclosure causes a computer to function as a control device for any of the indoor units described above.

[0011] According to the present disclosure, it is possible to provide an indoor unit control device that can prevent leaked refrigerant from accumulating in a specific area by ensuring a desired air volume, an indoor unit equipped with the same, a control method for an indoor unit, and a control program for an indoor unit.

[0012] 1 is a perspective view of an indoor unit of an air conditioning apparatus according to the present embodiment; FIG. 2 is a longitudinal cross-sectional view of an indoor unit according to the present embodiment; FIG. 3 is a longitudinal cross-sectional view of an indoor unit according to the present embodiment; FIG. 4 is a longitudinal cross-sectional view of an indoor unit according to the present embodiment; FIG. 5 is a diagram showing an example of the hardware configuration of a control device for an indoor unit according to the present embodiment; FIG. 6 is a functional configuration diagram showing an example of the functions of a control device for an indoor unit according to the present embodiment; FIG. 7 is an example of refrigerant distribution inside an indoor unit when refrigerant leaks into the indoor unit; FIG. 8 is an example of a case where the direction of a flap provided in the indoor unit is controlled to face vertically downward; FIG. 9 is an example of a case where the direction of a flap provided in the indoor unit is controlled to reciprocate between facing vertically downward and a predetermined direction.

[0013] An embodiment of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to this embodiment, and when there are multiple embodiments, it also includes configurations that combine the embodiments. In the following description, "up" and "upper" refer to the upper side in the vertical direction, and "lower" and "lower" refer to the lower side in the vertical direction, and the vertical direction is not precise and may include errors.

[0014] FIG. 1 is a perspective view of an indoor unit 1 of an air conditioning apparatus 100 according to this embodiment. FIGS. 2 to 4 are longitudinal cross-sectional views of the indoor unit 1 according to this embodiment. The longitudinal cross-sectional views of FIGS. 2 to 4 are views of the indoor unit 1 taken along section line II-II in FIG. 1. Note that, in this embodiment, an example in which the indoor unit is applied to a wall-mounted indoor unit will be described, but the type of indoor unit is not limited to a wall-mounted type, and it goes without saying that the indoor unit can also be applied to other types of indoor units, such as a ceiling-mounted type or a free-standing type. Also, in FIGS. 3 and 4, some of the reference numerals shown in FIG. 2 have been omitted.

[0015] In this embodiment, the direction that is horizontal when installed (the longitudinal direction of the indoor unit 1) is referred to as the left-right direction, the direction that is vertical when installed is simply referred to as the up-down direction, and the direction perpendicular to these left-right and up-down directions is referred to as the front-to-rear direction. Note that the front side when installed is the front side in the front-to-rear direction.

[0016] As shown in FIG. 1 , the indoor unit 1 includes a housing 2 having a horizontally elongated rectangular parallelepiped shape. As shown in FIG. 2 , the housing 2 defines an internal space S therein. The housing 2 includes a base 3 that forms the rear side of the housing 2, a front panel 4 that covers the front side of the base 3, an inlet panel 6 that covers a front opening 5 of the front panel 4, an outlet grill 7 that is disposed between the front and bottom surfaces of the front panel 4, and a ceiling panel (ceiling portion) 8 that defines the upper portion of the internal space S. The ceiling panel 8 extends substantially horizontally. The indoor unit 1 includes an air filter (filter) 15 that is disposed above an air duct 20 and that captures dust contained in fluid passing through the air duct 20, and a cleaning device (cleaning mechanism) 30 that cleans the air filter.

[0017] The base 3 is integrally molded with an air flow path wall 9 that forms an outlet flow path 20A for air blown out from a crossflow fan (fan) 18. An intake port 12 is formed in the ceiling panel 8. The inlet panel 6 is installed so that it can move up and down by driving force from an electric motor (panel drive unit) (not shown). An opening 13 is provided in the lower part of the inlet panel 6. In addition, an air outlet 14 is opened in the outlet grill 7 disposed between the front and bottom surfaces of the front panel 4.

[0018] An air filter (filter) 15 is disposed inside the housing 2. Furthermore, a plate-fin tube-type indoor heat exchanger (heat exchanger) 17 is disposed downstream of the air filter 15 in the ventilation duct 20, which is the air flow path inside the indoor unit 1. Details of the air filter 15 will be described later. As shown in FIG. 2 , the indoor heat exchanger 17 is divided into a first heat exchanger 17A disposed on the front side and a second heat exchanger 17B disposed on the rear side. Furthermore, the lower portion of the first heat exchanger 17A on the front side has a bent-up shape. The upper ends of the first heat exchanger 17A and the second heat exchanger 17B are connected by a bracket. The first heat exchanger 17A is composed of three panel-shaped heat exchangers, which are arranged so that they overlap when viewed from the front. The first heat exchanger 17A is composed of two panel-shaped heat exchangers, which are arranged so that they overlap when viewed from the front.

[0019] The indoor heat exchanger 17, which is divided or folded into multiple pieces, is arranged so that its cross section forms an inverted V shape from the lower front surface to the upper and rear surfaces inside the housing 2. In other words, the first heat exchanger 17A arranged on the front side of the indoor heat exchanger 17 and the second heat exchanger 17B arranged on the rear side are arranged so that their upper ends are close to each other and the distance between them gradually increases as they go downward, forming an inverted V shape.

[0020] The indoor heat exchanger 17 also has a plurality of tubes 17C through which a refrigerant flows and which extend in a predetermined direction (the longitudinal direction of the indoor unit 1), and a plurality of plate-shaped fins arranged perpendicular to the extension direction of the tubes 17C.

[0021] A cross-flow fan 18 having an elongated cylindrical shape is disposed downstream of the indoor heat exchanger 17 so as to be rotatable about its central axis (horizontal axis). The cross-flow fan 18 is rotated by the driving force of a fan motor (not shown), thereby introducing air into the interior space S from the air intake 12, etc. (arrow A1 in FIG. 1 ) and supplying the introduced air to the indoor heat exchanger 17.

[0022] A stabilizer 19 molded integrally with the outlet grille 7 is disposed downstream and forward of the crossflow fan 18. The stabilizer 19 and the air flow path wall 9 molded on the base 3 form an outlet flow path 20A leading to the outlet 14. After heat exchange in the indoor heat exchanger 17, the air is discharged through the outlet 14 to the outside of the housing 2 via the outlet flow path 20A (arrow A2 in FIG. 1 ).

[0023] The outlet grille 7 is integrally molded with a drain pan 21 that receives drain water flowing down from the first heat exchanger 17A that constitutes the indoor heat exchanger 17, together with a stabilizer 19. The outlet grille 7 is also rotatably provided with a plurality of vertical louvers 22 that adjust the direction of the temperature-controlled air blown out from the air outlet 14 in the left-right direction, and is also rotatably provided with horizontal flaps (flaps) 23 that adjust the direction of the temperature-controlled air in the up-down direction.

[0024] Next, the air filter 15 and the cleaning device (cleaning mechanism) 30 according to this embodiment will be described in detail. In the following description, the "normal state" refers to a state other than a state in which the indoor unit 1 is performing a cleaning operation in which the cleaning device 30 cleans the air filter 15. The cleaning operation is performed by a control unit 211 included in a control device 200, which will be described later.

[0025] In the normal state, the air filter 15 is disposed between the air intake 12 and the indoor heat exchanger 17 so as to cover the indoor heat exchanger 17 from above. Specifically, in the normal state, the air filter 15 is disposed below the ceiling panel 8 and above the indoor heat exchanger 17. The air filter 15 covers substantially the entire area of ​​the indoor heat exchanger 17 in the left-right direction (the longitudinal direction of the indoor unit 1). In the normal state, the rear portion of the air filter 15 is adjacent to the rear end of the ceiling panel 8 and extends along the ceiling panel 8. Furthermore, the front portion of the air filter 15 is disposed along the first heat exchanger 17A. In other words, the front portion of the air filter 15 is curved downward in the normal state.

[0026] The air filter 15 has a plurality of filter gears 26 that protrude upward from the upper surface (upper surface in normal condition) of both ends in the left-right direction (longitudinal direction of the indoor unit 1), and a collection section (not shown) provided in the central region in the left-right direction.

[0027] The plurality of filter gears 26 are arranged side by side at approximately equal intervals across approximately the entire area of ​​the air filter 15 in the front-to-rear direction (movement direction). The plurality of filter gears 26 are configured to engage with gear portions of a cleaning device 30, which will be described later. The collection portion is a sheet-like member having a plurality of linear filter holes (not shown) that allow air to pass through and collect dust and the like contained in the air.

[0028] The indoor unit 1 includes a cleaning device 30 that cleans the air filter 15 and a guide portion 40 that defines the movement path of the air filter 15 .

[0029] The cleaning device 30 is disposed in the internal space S. The cleaning device 30 is provided in front of the indoor heat exchanger 17. Specifically, the cleaning device 30 is provided in front of the bent portion of the first heat exchanger 17A. The cleaning device 30 includes two gear units (movement devices) (not shown) provided at both left-right ends, a cleaning unit motor (not shown) that rotates and drives the gear units, a first brush unit (brush) 31 provided in the center region in the left-right direction, a second brush unit (brush) 32 provided opposite the first brush unit 31, and a dust box 33 that discharges dust and other particles collected by the first brush unit 31 and the second brush unit 32. The second brush unit 32 and the dust box 33 are provided below the first brush unit 31. The relative positions of the components of the cleaning device 30 are not limited to this example and may be changed as appropriate.

[0030] Each gear portion rotates around a central axis extending in the left-right direction by the driving force from the cleaning unit motor. Each gear portion is configured to engage with a filter gear 26. In a normal state, each gear engages with the filter gear 26 that is located furthest forward among the multiple filter gears 26 portions.

[0031] The first brush part 31 has a cylindrical member extending in the left-right direction and a brush (not shown) made of a plurality of fibrous members attached to the outer peripheral surface of the cylindrical member. The first brush part 31 comes into contact with the collecting part to push the dust and other particles collected by the collecting part downward.

[0032] The second brush part 32 is a brush (not shown) made up of a plurality of fibrous members extending radially, which rotates around a central axis extending in the left-right direction, and sweeps the dust, etc. pushed out by the first brush part 31 into the dust box 33. The second brush part 32 captures the dust, etc. scraped off by the first brush part 31. In other words, the second brush part 32 captures the dust, etc. adhering to the brush of the first brush part 31, for example, like a comb. The second brush part 32 sweeps the collected dust, etc. into the dust box 33.

[0033] The configuration of the cleaning device 30 is not limited to the above-described configuration. For example, the second brush unit 32 may not be provided. In this configuration, the brush of the first brush unit 31 directly sweeps the dust and other particles scraped from the collection unit into the dust box 33. Alternatively, for example, the second brush unit 32 and the dust box 33 may be provided above the first brush unit 31. In this configuration, the brush of the first brush unit 31 contacts the collection unit of the air filter 15, thereby scraping the dust and other particles collected by the collection unit from the collection unit. In other words, the brush comes into contact with the upper surface of the collection unit (the upper surface in the normal state), which is prone to dust adhesion, and scoops up the dust and other particles adhering to the upper surface of the collection unit. The second brush unit 32 then collects the dust and other particles scraped by the first brush unit 31. In other words, the second brush unit 32 collects the dust and other particles adhering to the brush of the first brush unit 31, like a comb. The second brush portion 32 sweeps away the collected dust and the like into a dust box 33 .

[0034] The guide portion 40 has a first guide portion 41 that holds the air filter 15 under normal conditions, and a second guide portion 42 that connects the air filter 15 to the gear portion of the cleaning device 30 during cleaning operation, and defines the movement path of the air filter 15 moved by the cleaning device 30.

[0035] The first guide portion 41 has a left guide portion that guides the filter gear 26 provided at the left end of the air filter 15, and a right guide portion that guides the filter gear 26 provided at the right end of the air filter 15. The left guide portion and the right guide portion are spaced apart in the left-right direction. The distance between the left guide portion and the right guide portion is approximately the same as the left-right length of the collection portion. In other words, the left guide portion and the right guide portion are arranged so as not to block air flow toward the collection portion. Because the left guide portion and the right guide portion have approximately the same configuration, they will be collectively described below as the first guide portion 41. In other words, the following description of the first guide portion 41 applies to both the left guide portion and the right guide portion.

[0036] The first guide portion 41 is composed of two rails that are spaced apart and generally parallel to each other, and the filter gear 26 of the air filter 15 is disposed in the space formed between the two rails, thereby enabling the filter gear 26 to be held. The first guide portion 41 is provided below the ceiling panel 8 and above the indoor heat exchanger 17. The rear portion of the first guide portion 41 is located close to the rear end of the ceiling panel 8 and is provided along the ceiling panel 8. The front portion of the first guide portion 41 is provided along the first heat exchanger 17A. That is, the front portion of the first guide portion 41 is curved downward in the normal state.

[0037] The front end of the first guide part 41 is located behind the gear part of the cleaning device 30 and near the rear end of the gear part. The front end of the first guide part 41 extends tangentially to the gear part. The length of the first guide part 41 in the extending direction is approximately the same as the length of the air filter 15 in the front-to-rear direction (the length from one end to the other end in the movement direction). In a normal state, the air filter 15 is held by the first guide part 41.

[0038] Similar to the first guide portion 41, the second guide portion 42 has a left guide portion that guides the filter gear 26 provided at the left end of the air filter 15, and a right guide portion that guides the filter gear 26 provided at the right end of the air filter 15. The left guide portion and the right guide portion are spaced apart in the left-right direction. The distance between the left guide portion and the right guide portion is approximately the same as the left-right length of the collection portion. Because the left guide portion and the right guide portion have approximately the same configuration, they will be collectively referred to as the second guide portion 42 in the following description.

[0039] The second guide portion 42 is composed of two spaced apart, generally parallel rails, and the filter gear 26 of the air filter 15 is disposed in the space formed between the two rails, thereby enabling the filter gear 26 to be held. The lower end of the second guide portion 42 is located in front of the gear portion and near the front end of the gear portion. The lower end of the second guide portion 42 extends tangentially to the gear portion. The second guide portion 42 extends upward from the lower end and curves rearward as it extends upward. The upper end of the second guide portion 42 is disposed within the internal space S.

[0040] The second guide portion 42 is positioned so as not to block the air passage 20 located between the air intake 12 and the indoor heat exchanger 17 (see FIGS. 2 to 4). The first guide portion 41 and the second guide portion 42 do not intersect. The first guide portion 41 and the second guide portion 42 are spaced apart and each has an independent configuration. In other words, the first guide portion 41 and the second guide portion 42 do not overlap.

[0041] Next, the operation of the cleaning device 30 during cleaning operation in this embodiment will be described. As described above, in the normal state, the air filter 15 is disposed in the first guide portion 41, and the filter gear 26 disposed at the front end (forward in the direction of movement) is engaged with the gear portion of the cleaning device 30.

[0042] When the cleaning operation starts, the cleaning motor is first driven. When the cleaning motor is driven, the gear unit rotates due to the driving force of the cleaning motor. At the same time as the gear unit rotates, the second brush unit 32 also begins to rotate. The gear unit rotates in a direction such that the lower half of the gear unit moves from rear to front. As the gear unit rotates, the air filter 15 moves. The front end of the air filter 15 initially moves a predetermined angle along the arc of the gear unit. At this time, the first brush unit 31 of the cleaning device 30 comes into contact with the collecting portion of the air filter 15, causing dust and other particles to be scraped out of the collecting portion. The scraped out dust and other particles are collected by the second brush unit 32 and then swept into the dust box 33. In this manner, dust and other particles are removed from the collecting portion of the air filter 15.

[0043] Next, the cleaning motor is driven again to rotate the gear unit again. At this time, the rotation direction of the gear unit is reversed from before. That is, the lower half of the gear unit is now moving from front to rear. As a result, the air filter 15 moves in the opposite direction from before, toward the first guide unit 41. Note that the cleaning device 30 also cleans the air filter 15 while it is moving toward the first guide unit 41. When the air filter 15 returns to being held in the first guide unit 41, the cleaning motor is stopped, and the cleaning operation ends.

[0044] The movement path of the air filter 15 during cleaning operation will be described in detail. When the cleaning operation starts, the air filter 15 first moves diagonally downward and forward along the first guide portion 41. When it reaches the cleaning device 30, the air filter 15 makes a U-turn along the lower half of the gear portion. That is, it makes a U-turn upward. After making the U-turn, the air filter 15 moves diagonally upward along the second guide portion 42. Position sensors PS1 and PS2 for determining the position of the air filter 15 are provided at predetermined positions along the second guide portion 42. For example, the position sensor PS1 may be provided near the center of the extension direction of the second guide portion 42, and the position sensor PS2 may be provided near the end of the second guide portion 42 opposite to the end on the cleaning device 30 side. Note that when the air filter 15 is stored in the first guide portion 41, the air filter 15 moves in the opposite direction. As such, the movement paths of the air filter 15 according to this embodiment do not intersect or overlap. In other words, they form a single path.

[0045] Next, the control device 200 of the indoor unit 1 according to this embodiment will be described. FIG. 5 is a diagram showing an example of the hardware configuration of the control device 200 of the indoor unit 1 according to this embodiment. As shown in FIG. 5, the control device 200 of the indoor unit 1 is a computer, and includes, for example, a CPU (Central Processing Unit: processor) 201, a main memory 202, a secondary storage 203, a communication interface 204, etc. The control device 200 of the indoor unit 1 may also include an input device 205 that accepts input from the user, a display 206, etc. These components are connected via, for example, a bus 208.

[0046] The main storage device 202 is composed of writable memory such as cache memory, RAM (Random Access Memory), etc., and is used as a work area for reading execution programs of the CPU 201 and writing processing data by the execution programs. The secondary storage device 203 is a non-transitory computer-readable storage medium. Examples of the secondary storage device 203 include magnetic disks such as HDDs (Hard Disk Drives), magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories such as SSDs (Solid State Drives).

[0047] 6 is a functional configuration diagram showing an example of functions of the control device 200 of the indoor unit 1 according to this embodiment. As shown in FIG. 6, the control device 200 of the indoor unit 1 includes a leakage detection unit 210 and a control unit 211.

[0048] A series of processes for realizing the various functions described below is stored in the secondary storage device 203 (see FIG. 5 ) in the form of a program (e.g., a boiler control program), for example, and the CPU 201 reads this program into the main storage device 202 and executes information processing and arithmetic processing to realize the various functions. Note that the program may be pre-installed in the secondary storage device 203, provided in a state stored in another computer-readable storage medium, or distributed via wired or wireless communication means. Examples of computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories.

[0049] The leak detection unit 210 is provided in the housing of the indoor unit 1 and detects refrigerant leaks. The leak detection unit 210 is, for example, a refrigerant leak sensor that detects the refrigerant concentration in a detection target area. The control device 200 detects a refrigerant leak, for example, when the refrigerant concentration detected by the leak detection unit 210 is equal to or greater than a predetermined threshold. Note that the leak detection unit 210 is not limited to a refrigerant leak sensor that detects refrigerant concentration, and may also detect parameters such as temperature and pressure to determine a refrigerant leak. The predetermined threshold is set as appropriate depending on the type of refrigerant, the operation settings of the indoor unit 1, user input, etc.

[0050] FIG. 7 shows an example of refrigerant distribution inside the indoor unit 1 when refrigerant leaks into the indoor unit 1. When refrigerant leaks into the indoor unit 1, the refrigerant concentration inside the housing differs, for example, as shown in the example of FIG. 7. In the example of FIG. 7, the hatching indicates that the refrigerant concentration is higher in specific areas area1 and area2 than in other areas. Therefore, in order to quickly detect a refrigerant leak, it is preferable to provide the leak detection unit 210 in a location where the refrigerant concentration in the specific areas area1 and area2 can be detected. Note that the location and number of leak detection units 210 may be changed as appropriate.

[0051] For example, when a refrigerant leak is detected by the leak detection unit 210 or when the amount of refrigerant leakage is equal to or greater than a predetermined threshold, the control unit 211 executes a cleaning operation to clean the air filter 15 using the cleaning device 30. For example, when the refrigerant concentration inside the indoor unit 1 detected by the leak detection unit 210 is equal to or greater than a predetermined threshold, the control unit 211 executes a cleaning operation to clean the air filter 15. By executing the cleaning operation, the control unit 211 drives the cleaning motor to retract the air filter 15 from the first guide part 41 located above the ventilation duct 20 to the second guide part 42, and removes dust from the air filter 15 using a brush.

[0052] Furthermore, the control unit 211 may be configured to determine whether to perform or stop the cleaning operation in accordance with the detection amount of the leakage detection unit 210, as well as detection signals from various sensors included in the indoor unit 1 and the operating state of the indoor unit 1. For example, the control unit 211 may be configured to perform the cleaning operation when the amount of refrigerant leakage detected by the leakage detection unit 210 is equal to or greater than a predetermined threshold, and to stop the cleaning operation when both the detection signal of the position sensor PS1 near the center position in the extension direction of the second guide part 42 and the detection signal of the position sensor PS2 near the end of the second guide part 42 on the cleaning device 30 side and the opposite end thereof are ON.

[0053] In addition, when the air filter 15 is retracted to the second guide section 42 and the leakage detection section 210 detects that the amount of refrigerant leakage is less than a predetermined threshold, the control section 211 may control the cleaning motor to position the air filter 15 on the ventilation duct 20.

[0054] The control unit 211 may also control various actuators such as the cross flow fan 18 and the cleaning motor provided in the cleaning device 30, depending on the detection signals of various sensors and the operating state of the indoor unit 1. The control unit 211 may also control the airflow direction of the vertical louvers 22 and horizontal flaps 23, depending on the detection signals of various sensors and the operating state of the indoor unit 1.

[0055] For example, when a refrigerant leak is detected by the leak detection unit 210, the control unit 211 may control the direction of the horizontal flap 23 provided in the indoor unit 1 to face vertically downward. Furthermore, when a refrigerant leak is detected by the leak detection unit 210, the control unit 211 controls the direction of the horizontal flap 23 provided in the indoor unit 1 to move back and forth between the vertically downward direction and a predetermined direction. In this way, by appropriately controlling the direction of the horizontal flap 23, it is possible to prevent leaked refrigerant from accumulating in a specific area in an air-conditioned environment.

[0056] The control device 200 may include, for example, an internal clock. The control device 200 may generate time information indicating the time on the clock at a predetermined timing. The time information may be information indicating the time elapsed from the predetermined timing. The control unit 211 may determine whether or not to perform a cleaning operation based on the time information.

[0057] (Impact of Cleaning Operation) Next, the effect of performing the cleaning operation on leaked refrigerant will be described. The cleaning operation is performed by the control unit 211 when the refrigerant concentration in the area to be detected by the leak detection unit 210 is equal to or greater than a predetermined threshold, or when the leak detection unit 210 detects a refrigerant leak.

[0058] In a state where the air filter 15 is present between the air intake 12 and the cross flow fan 18 (see FIG. 2), the air filter 15 acts as a barrier in the air path, which is the direction of airflow inside the indoor unit 1. Furthermore, if the air filter 15 becomes clogged with dust or dirt, the amount of air flowing from the air intake 12 to the cross flow fan 18 will decrease. If refrigerant leaks in this state, even if the cross flow fan 18 is rotated, a sufficient amount of air may not be secured, and the leaked refrigerant may not be agitated to a concentration below the ignition point.

[0059] When the cleaning operation is performed in this embodiment, the air filter 15 arranged in the first guide portion 41 is wound up by the cleaning motor provided in the cleaning device 30, and the dust and dirt collected by the air filter 15 is removed by the first brush portion 31 and the second brush portion 32 and sent to the second guide portion 42 (see FIGS. 3 and 4). In other words, the air filter 15 is no longer present between the suction port 12 and the cross flow fan 18.

[0060] In this way, cleaning device 30 removes dust and dirt from the collection portion of air filter 15 using air filter 15, and also moves air filter 15 out from between suction port 12 and cross flow fan 18. This reduces ventilation resistance, and allows cross flow fan 18 to rotate without reducing the amount of air flowing from suction port 12 to cross flow fan 18, thereby agitating the leaked refrigerant to below an ignition concentration.

[0061] Note that after the air filter 15 is sent to the second guide section 42 during the cleaning operation, the air filter 15 may be placed back into the first guide section 41. In this case, the air filter 15 is not clogged because it has been cleaned by the cleaning device 30. Therefore, even if the cleaned air filter 15 is placed back into the first guide section 41, the amount of air flowing from the suction port 12 to the crossflow fan 18 does not decrease. Therefore, by rotating the crossflow fan 18, the leaked refrigerant can be agitated to a concentration below the ignition concentration. Alternatively, the air filter 15 may be placed in the second guide section 42 until the amount of refrigerant leakage detected by the leak detection section 210 falls below a predetermined threshold.

[0062] (Regarding Flap Direction Control) In the present embodiment, the control unit 211 may change the direction of the horizontal flap 23, for example, when the leak detection unit 210 detects a refrigerant leak or when the amount of refrigerant leakage is equal to or greater than a threshold. FIG. 8 illustrates an example of controlling the direction of the flap provided in the indoor unit 1 to face vertically downward. When the leak detection unit 210 detects a refrigerant leak, the control unit 211 may control the direction of the horizontal flap 23 provided in the indoor unit 1 to face vertically downward. When a refrigerant leak occurs in an air-conditioned environment, most of the refrigerant (e.g., R32) that is heavier than air will accumulate near the floor. Therefore, when the leak detection unit 210 detects a refrigerant leak, i.e., when the refrigerant accumulates near the floor, the control unit 211 controls the direction of the horizontal flap 23 to face vertically downward. This control agitates the refrigerant that has leaked in the air-conditioned environment. This makes it possible to prevent refrigerant that has leaked into an air-conditioned environment from accumulating in a particular area.

[0063] FIG. 9 illustrates an example of controlling the direction of the flap provided in the indoor unit 1 to reciprocate between a vertically downward direction and a predetermined direction. Instead of the example illustrated in FIG. 8 , the control unit 211 may control the direction of the horizontal flap 23 provided in the indoor unit 1 to reciprocate between a vertically downward direction and a predetermined direction when the leak detection unit 210 detects a refrigerant leak. For example, when the leak detection unit 210 detects a refrigerant leak, i.e., when refrigerant accumulates near the floor, the control unit 211 controls the direction of the horizontal flap 23 to reciprocate between a vertically downward direction and a horizontal direction. This control agitates the refrigerant leaked in the air-conditioned environment. This prevents the refrigerant leaked in the air-conditioned environment from accumulating in a specific area. Note that the predetermined direction is not limited to the horizontal direction and may be determined based on the operation settings of the indoor unit 1 input by the user. The predetermined direction may also be determined based on the detection results of the leak detection unit 210. The predetermined direction may also be set appropriately by combining other known techniques.

[0064] (Regarding the timing of performing the cleaning operation) In the present embodiment, the control unit 211 may perform the cleaning operation according to the operating state of the indoor unit 1. For example, the control unit 211 may perform the cleaning operation when the crossflow fan 18 provided in the indoor unit 1 is driven. Specifically, the control unit 211 retracts the air filter 15 from above the ventilation duct 20 while driving the crossflow fan 18. In other words, since there is no obstruction above the ventilation duct 20, the speed of the intake airflow can be increased. In this way, the desired air volume can be ensured with respect to the air volume taken in by the indoor unit 1 and the air volume blown out from the indoor unit 1. In other words, it is possible to prevent refrigerant that has leaked into the air-conditioned environment from accumulating in a specific area.

[0065] Furthermore, the control unit 211 may be configured to execute a cleaning operation when the indoor unit 1 is stopped after operating for a predetermined time. After the indoor unit 1 has operated for a predetermined time, there is a high possibility that a predetermined amount of dust or more will adhere to the air filter 15. By having the control unit 211 execute a cleaning operation after the indoor unit 1 has operated for a predetermined time, the period during which the indoor unit 1 operates with a clogged filter is shortened. This prevents a decrease in the volume of air taken in by the indoor unit 1 and the volume of air blown out from the indoor unit 1. In other words, by ensuring the desired volume of air, it is possible to prevent leaked refrigerant from accumulating in a specific area in the air-conditioned environment.

[0066] (Other) The control unit 211 may also control the rotation speed of the cross flow fan 18 in accordance with the amount of refrigerant leakage detected by the leakage detection unit 210. For example, a rotation speed setting value for the cross flow fan 18 corresponding to the difference between the amount of refrigerant leakage detected by the leakage detection unit 210 and a predetermined threshold value may be stored in advance in the secondary storage device 203. The control unit 211 may then extract from the secondary storage device 203 the rotation speed setting value for the cross flow fan 18 corresponding to the detection result of the leakage detection unit 210 and control the cross flow fan 18. This makes it possible to achieve both agitation of refrigerant leaked in the air-conditioned environment and efficient operation of the indoor unit 1.

[0067] This embodiment provides the following advantages. When the leak detection unit 210 detects a refrigerant leak inside the indoor unit 1, the control unit 211 included in the control device 200 controls the cleaning device 30 to clean the air filter 15. Specifically, the cleaning unit motor included in the cleaning device 30 rotates to transport the air filter 15 between the first brush unit 31 and the second brush unit 32 along the ventilation duct 20, and each brush unit removes dust and other particles adhering to the collection section of the air filter 15. Cleaning the air filter 15 in this manner reduces clogging of the air filter 15 and prevents a decrease in the volume of air passing through the ventilation duct 20. This ensures a desired volume of air blown out from the indoor unit 1 and prevents leaked refrigerant from accumulating in a specific area in an air-conditioned environment.

[0068] Furthermore, during cleaning operation, the control unit 211 drives the cleaning motor to retract the air filter 15 from the first guide portion 41 to the second guide portion 42. That is, when the leak detection unit 210 detects a refrigerant leak inside the indoor unit 1, the control unit 211 retracts the air filter 15 from the ventilation duct 20. This prevents a decrease in the volume of air taken in by the indoor unit and the volume of air blown out from the indoor unit. This prevents the leaked refrigerant from accumulating in the air-conditioned environment. Note that, in this embodiment, an example has been described in which the cleaning device 30 moves the air filter 15 and cleans it, but the present invention is not limited to this example. Alternatively, a mechanism for cleaning the air filter 15 while it is fixed in place may be used.

[0069] Furthermore, when the leak detection unit 210 detects a refrigerant leak inside the indoor unit 1, the control unit 211 may control the horizontal flap 23 of the indoor unit 1 to switch its direction. This allows air to be blown evenly over a wide area, including a specific area where leaked refrigerant may accumulate in an air-conditioned environment. This makes it possible to prevent leaked refrigerant from accumulating in a specific area in an air-conditioned environment.

[0070] The control unit 211 may also be configured to execute cleaning operation when driving the crossflow fan 18 provided in the indoor unit 1. In this case, the desired air volume can be ensured with respect to the air volume taken in by the indoor unit and the air volume blown out from the indoor unit, and leaked refrigerant can be prevented from accumulating in a specific area in the air-conditioned environment.

[0071] The control unit 211 may also be configured to execute a cleaning operation when the indoor unit 1 is stopped after operating for a predetermined period of time. In other words, the control unit 211 executes a cleaning operation at a timing when there is a high possibility that the air filter 15 is clogged with dust or the like, thereby shortening the period during which the filter is clogged. This makes it possible to ensure the desired air volume for the air taken in by the indoor unit 1 and the air volume blown out from the indoor unit 1. This makes it possible to prevent leaked refrigerant from accumulating in a specific area in the air-conditioned environment.

[0072] The present disclosure is not limited to the above-described embodiment, and various modifications are possible within the scope of the invention. It is also possible to appropriately combine known air conditioning control technologies.

[0073] (Additional Notes) The indoor unit control device, indoor unit equipped with the same, indoor unit control method, and indoor unit control program described in each of the embodiments described above may be understood, for example, as follows: An indoor unit control device (200) according to a first aspect of the present disclosure is a control device for an indoor unit (1) that is provided on an air duct (20) and that is equipped with a filter (15) that captures dust contained in fluid passing through the air duct, and a cleaning mechanism (30) that cleans the filter, and that is provided within a housing of the indoor unit and is equipped with a leak detection unit (210) that detects refrigerant leaks, and a control unit (211) that, when the leak is detected, executes a cleaning operation to clean the filter using the cleaning mechanism.

[0074] According to the indoor unit control device of the present disclosure, when a refrigerant leak is detected by the leak detection unit, the control unit executes a cleaning operation to clean the filter using the cleaning mechanism. When a refrigerant leak is detected, the cleaning mechanism cleans the filter that has captured dust, reducing filter clogging. This prevents a decrease in the air volume taken in by the indoor unit and the air volume blown out from the indoor unit. This ensures a desired air volume, preventing leaked refrigerant from accumulating in a specific area in the air-conditioned environment.

[0075] The indoor unit control device according to a second aspect of the present disclosure is the first aspect, wherein the leakage detection unit detects refrigerant leakage when the amount of refrigerant leakage is equal to or greater than a predetermined threshold.

[0076] According to the indoor unit control device of the present disclosure, the leak detection unit detects a refrigerant leak when the amount of refrigerant leakage is equal to or greater than a predetermined threshold. In this way, the leak detection unit detects a refrigerant leak based on a quantitative comparison, making it possible to more accurately grasp the extent of the refrigerant leak.

[0077] In the control device for an indoor unit according to a third aspect of the present disclosure, in either the first or second aspect, the cleaning mechanism comprises a winding mechanism that retracts the filter from the ventilation duct to an evacuation path (42), and brushes (31, 32) that are provided on the path of the evacuation path and remove dust from the filter, and the cleaning operation is an operation in which the winding mechanism retracts the filter to the evacuation path and the brush removes dust from the filter.

[0078] According to the indoor unit control device of the present disclosure, the cleaning mechanism includes a winding mechanism that retracts the filter from the ventilation duct to an evacuation path and a brush that is located on the path of the evacuation path and removes dust collected by the filter from the filter. The cleaning operation involves retracting the filter to the evacuation path using the winding mechanism and removing dust from the filter using the brush. When the control unit executes the cleaning operation, the winding mechanism retracts the filter to the evacuation path and removes the filter from the ventilation duct. This prevents a decrease in the volume of air taken in by the indoor unit and the volume of air blown out from the indoor unit. This prevents refrigerant leaking into the air-conditioned environment from accumulating. Furthermore, during the cleaning operation, obstructions (filters) from the ventilation duct can be removed and the filter can be cleaned simultaneously.

[0079] In the control device for an indoor unit according to a fourth aspect of the present disclosure, in the third aspect, the control unit controls the winding mechanism to position the filter on the ventilation path when the filter is retracted into the retraction path and the leakage detection unit does not detect the leakage.

[0080] In the indoor unit control device according to the present disclosure, if the leak detection unit detects no refrigerant leak, the control unit controls the winding mechanism to place the filter in the ventilation duct. In this way, if no refrigerant leak is detected, the cleaned filter can be placed in the ventilation duct again. Therefore, even if a filter is placed in the ventilation duct, it is possible to prevent a difference between the volume of air drawn in and the volume of air blown out by the indoor unit.

[0081] In the control device for an indoor unit according to a fifth aspect of the present disclosure, in any of the first to fourth aspects, when the leakage is detected, the control unit controls the direction of a flap (23) provided in the indoor unit to be vertically downward.

[0082] According to the indoor unit control device of the present disclosure, when a refrigerant leak is detected, the direction of a flap provided in the indoor unit is controlled to face vertically downward. Because the leaked refrigerant is heavier than air, it accumulates vertically downward in the air-conditioned environment. By controlling the flap to face vertically downward, the control unit can intensively blow air toward a specific area where the refrigerant is accumulating. This prevents the leaked refrigerant from accumulating in a specific area in the air-conditioned environment.

[0083] In the control device for an indoor unit according to a sixth aspect of the present disclosure, in any of the first to fourth aspects, when the leakage is detected, the control unit controls the direction of a flap (23) provided in the indoor unit to reciprocate between a vertically downward direction and a predetermined direction.

[0084] According to the indoor unit control device of the present disclosure, when a refrigerant leak is detected, the direction of a flap provided in the indoor unit is controlled to reciprocate between a vertically downward direction and a horizontal direction. Because the leaked refrigerant is heavier than air, it accumulates vertically downward in the air-conditioned environment. In such a case, the control unit controls the direction of the flap to reciprocate between a vertically downward direction and a horizontal direction. This allows air to be blown evenly over a wide area, including a specific area where the leaked refrigerant accumulates in the air-conditioned environment. This prevents the leaked refrigerant from accumulating in a specific area in the air-conditioned environment.

[0085] The control device for an indoor unit according to a seventh aspect of the present disclosure is any one of the first to sixth aspects, wherein the control unit executes the cleaning operation when a fan (18) provided in the indoor unit is driven.

[0086] According to the indoor unit control device of the present disclosure, the control unit executes a cleaning operation when the indoor unit's fan is driven. That is, the control unit retracts the filter from the ventilation duct while driving the fan. This removes obstructions from the ventilation duct, allowing the intake air speed to increase. In this way, the desired air volume can be ensured for both the air intake and the air blown out by the indoor unit. This prevents leaked refrigerant from accumulating in a specific area in the air-conditioned environment.

[0087] The indoor unit control device according to an eighth aspect of the present disclosure is any one of the first to seventh aspects, wherein the control unit executes the cleaning operation when the indoor unit is stopped after operating for a predetermined period of time.

[0088] According to the indoor unit control device of the present disclosure, the control unit executes a cleaning operation when the indoor unit stops after operating for a predetermined period of time. After the indoor unit has operated for a predetermined period of time, there is a high possibility that a predetermined amount of dust or more will adhere to the filter. By executing a cleaning operation after the indoor unit has operated for a predetermined period of time, the control unit can shorten the period during which the filter becomes clogged. This ensures that the desired air volume is maintained for both the air intake and the air output of the indoor unit. This prevents leaked refrigerant from accumulating in a specific area in the air-conditioned environment.

[0089] An indoor unit according to a ninth aspect of the present disclosure includes the indoor unit control device according to any one of the first to eighth aspects, the filter, and the cleaning mechanism.

[0090] A control method for an indoor unit according to a tenth aspect of the present disclosure is a control method for an indoor unit (1) that is provided on an air duct (20) and includes a filter (15) that captures dust contained in a fluid passing through the air duct, and a cleaning mechanism (30) that cleans the filter, and includes a leakage detection step that detects a refrigerant leak in a housing of the indoor unit, and a control step that, when the leakage is detected, executes a cleaning operation to clean the filter using the cleaning mechanism.

[0091] A control program for an indoor unit according to an eleventh aspect of the present disclosure causes a computer to function as the control device for the indoor unit according to any one of the first to eighth aspects.

[0092] DESCRIPTION OF SYMBOLS 1 Indoor unit 2 Housing 3 Base 4 Front panel 5 Front opening 6 Inlet panel 7 Outlet grill 8 Ceiling panel 9 Air flow path wall 12 Intake port 13 Opening 14 Outlet port 15 Air filter 17 Indoor heat exchanger 17A First heat exchanger 17B Second heat exchanger 17C Tube 18 Cross flow fan 19 Stabilizer 20 Ventilation path 20A Outlet flow path 21 Drain pan 22 Vertical louver 23 Horizontal flap 26 Filter gear 30 Cleaning device 31 First brush section 32 Second brush section 33 Dust box 40 Guide section 41 First guide section 42 Second guide section 100 Air conditioning device 200 Control device 201 CPU 202 Main memory device 203 Secondary memory device 204 Communication interface 205 Input device 206 Display 208 Bus 210 Leak detection unit 211 Control unit PS1, PS2 Position sensor S Internal space area1, area2 Area

Claims

1. A control device for an indoor unit that is provided with a filter disposed on an air duct for capturing dust contained in a fluid passing through the air duct, and a cleaning mechanism for cleaning the filter, the control device comprising: a leakage detection unit disposed within the housing of the indoor unit for detecting refrigerant leakage; and a control unit that, when the leakage is detected, executes a cleaning operation to clean the filter using the cleaning mechanism.

2. The indoor unit control device according to claim 1, wherein the leakage detection unit detects refrigerant leakage when the amount of refrigerant leakage is equal to or greater than a predetermined threshold value.

3. The control device for an indoor unit according to claim 1, wherein the cleaning mechanism comprises a winding mechanism that retracts the filter from the ventilation duct to an evacuation path, and a brush that is provided on the path of the evacuation path and removes dust from the filter, and the cleaning operation is an operation in which the winding mechanism retracts the filter to the evacuation path and the brush removes dust from the filter.

4. The control device for an indoor unit according to claim 3, wherein the control unit controls the winding mechanism to position the filter on the ventilation path when the leak detection unit does not detect the leak while the filter is retracted into the retraction path.

5. The control device for an indoor unit according to claim 1, wherein the control unit controls the direction of a flap provided in the indoor unit to face vertically downward when the leakage is detected.

6. The control device for an indoor unit according to claim 1, wherein the control unit controls the direction of a flap provided in the indoor unit to reciprocate between a vertically downward direction and a predetermined direction when the leakage is detected.

7. The control device for an indoor unit according to claim 2, wherein the control unit executes the cleaning operation when a fan provided in the indoor unit is driven.

8. The control device for an indoor unit according to claim 1, wherein the control unit executes the cleaning operation when the indoor unit stops after operating for a predetermined period of time.

9. An indoor unit comprising: an indoor unit control device according to any one of claims 1 to 8; the filter; and the cleaning mechanism.

10. A control method for an indoor unit provided with a filter disposed on an air duct for capturing dust contained in a fluid passing through the air duct, and a cleaning mechanism for cleaning the filter, the control method comprising: a leakage detection step for detecting a refrigerant leak within the casing of the indoor unit; and a control step for executing a cleaning operation to clean the filter using the cleaning mechanism when the leakage is detected.

11. A control program for an indoor unit that causes a computer to function as a control device for an indoor unit according to any one of claims 1 to 8.

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