Air conditioner

Abstract

The purpose of the invention is to reduce the number of illuminating elements. The invention proposes an air conditioner housing (10) comprising an air intake (11) and multiple air exhaust (12) elements. The illuminating element (91) is constructed to emit UVC toward the path P located between the air intake (11) and the large dust filter (60). The UVC is emitted not toward the air intake (11) but toward the large dust filter (60), which is located at the upper end of the path P, through the emission area R through which the UVC passes in the path P.

Description

air conditioner

[0001] The present disclosure relates to an air conditioner.

[0002] Air conditioners that sterilize by irradiating ultraviolet light are known. The air conditioner disclosed in Patent Document 1 includes an indoor unit having multiple lamps (irradiation units) that irradiate light containing ultraviolet light. The underside of the indoor unit is provided with a rectangular air inlet and four air outlets surrounding the air inlet. The indoor unit has a casing, a blower (fan) located in the center of the casing, and a heat exchanger arranged in a ring shape surrounding the blower and corresponding to the four air outlets. A ring-shaped drain pan is located below the heat exchanger to collect water droplets from the heat exchanger. Multiple lamps located near the upper end of the heat exchanger irradiate light containing ultraviolet light toward the drain pan.

[0003] Japanese Patent Application Laid-Open No. 2001-324195

[0004] In the air conditioner disclosed in Patent Document 1, an irradiation unit is used for each of the four air outlets, which results in a problem of a large number of parts.

[0005] An object of the present disclosure is to provide an air conditioner with a small number of irradiation units.

[0006] An air conditioner according to a first aspect of the present disclosure includes a casing having an air inlet and a plurality of air outlets, a fan disposed within the casing and generating an airflow within the casing from the air inlet to the air outlets, and an irradiation unit disposed within the casing and irradiating ultraviolet light. The irradiation unit irradiates ultraviolet light into a space downstream of the air inlet and upstream of the fan in the direction of the airflow.

[0007] According to the first aspect of the present disclosure, the number of irradiation units can be reduced.

[0008] The air conditioner according to a second aspect of the present disclosure may be of the first aspect, and may be a ceiling-mounted type. In this case, the sterilization effect of the air near the ceiling can be enhanced.

[0009] In the air conditioner according to a third aspect of the present disclosure, in the second aspect, the direction of ultraviolet light emitted from the irradiation unit may be directed vertically upward from the horizontal. In this case, leakage of ultraviolet light from the air inlet to the outside can be suppressed. Consequently, exposure of workers performing maintenance work inside the casing to ultraviolet light can be suppressed.

[0010] According to a fourth aspect of the present disclosure, in the air conditioner of any of the first to third aspects, the air inlet is rectangular, and a passage for the airflow formed by four sides is provided from the air inlet to the fan, and the irradiation unit may be arranged on one of the four sides of the air inlet excluding the four corners, or on one of the four sides of the passage excluding the four corners, and irradiate ultraviolet light into the passage. In this case, it is possible to reduce the area where the ultraviolet light intensity is weak.

[0011] In the air conditioner according to a fifth aspect of the present disclosure, in the fourth aspect, the irradiation unit may be disposed at a position excluding the center of each of the four sides of the air inlet, or at a position excluding the center of each of the four faces of the passage in a direction connecting both ends of each face. In this case, the area where the ultraviolet light intensity is weak can be further reduced.

[0012] According to a sixth aspect of the present disclosure, in the air conditioner of the fourth or fifth aspect, the irradiation unit may include a first irradiation unit arranged on a first side of the four sides of the air inlet or a first side of the four faces of the passage, and a second irradiation unit arranged on a second side opposite the first side of the four sides of the air inlet or a second side opposite the first side of the four faces of the passage. In this case, it is possible to reduce areas in the passage where the intensity of ultraviolet light is insufficient.

[0013] The air conditioner according to a seventh aspect of the present disclosure is the air conditioner of any of the first to sixth aspects above, further comprising a first filter disposed downstream of the air inlet and upstream of the fan in the direction of the airflow within the casing, wherein the irradiation unit irradiates ultraviolet light into a space upstream of the first filter in the direction of the airflow. In this case, the first filter and the air passing through the first filter can be sterilized.

[0014] The air conditioner according to an eighth aspect of the present disclosure is the air conditioner of any of the first to seventh aspects, and may further include a member that restricts ultraviolet light emitted from the irradiation unit from being directed toward the air inlet. In this case, it is possible to prevent ultraviolet light from leaking to the outside through the air inlet.

[0015] According to a ninth aspect of the present disclosure, in the air conditioner of any one of the first to eighth aspects, the irradiation unit may include a UVC-LED. In this case, the sterilization effect can be enhanced.

[0016] The air conditioner according to a tenth aspect of the present disclosure is the air conditioner of any of the first to sixth aspects above, and may further include a second filter disposed within the casing downstream of the fan in the direction of the airflow, and a sterilization unit disposed within the casing for sterilizing a space downstream of the air inlet and upstream of the fan in the direction of the airflow. In this case, air drawn in through the air inlet is sterilized by the sterilization unit and then guided to the fan and the second filter. This prevents bacteria and viruses from adhering to the fan and the second filter, thereby maintaining the hygienic state of the fan and the second filter.

[0017] The air conditioner according to an eleventh aspect of the present disclosure is the air conditioner of the tenth aspect, further comprising a first filter disposed downstream of the air inlet and upstream of the fan in the direction of the airflow within the casing. In this case, the air drawn in through the air inlet is purified in advance by the first filter before being guided to the fan and the second filter. This makes it possible to suppress deterioration of the second filter.

[0018] In the air conditioner according to a twelfth aspect of the present disclosure, in the eleventh aspect, the minimum particle size for which the second filter achieves a predetermined collection efficiency may be smaller than the minimum particle size for which the first filter achieves the predetermined collection efficiency. In this case, since the first filter captures relatively large particles, clogging of the second filter can be suppressed.

[0019] According to a thirteenth aspect of the present disclosure, in the air conditioner of the eleventh or twelfth aspect, the sterilization unit may include the irradiation unit. In this case, a high sterilization effect can be obtained.

[0020] According to a fourteenth aspect of the present disclosure, in the air conditioner of the thirteenth aspect, the irradiation unit may irradiate the first filter with ultraviolet light. In this case, bacteria and viruses adhering to the first filter are removed by irradiation with ultraviolet light, thereby suppressing a decrease in the sterilization ability of the first filter.

[0021] According to a fifteenth aspect of the present disclosure, in the air conditioner of any of the eleventh to fourteenth aspects, the air conditioner further includes a third filter disposed downstream of the air inlet and upstream of the first filter in the direction of the airflow within the casing, wherein the minimum particle size at which the third filter achieves a predetermined collection efficiency may be larger than the minimum particle size at which the first filter achieves the predetermined collection efficiency. In this case, the air drawn in through the air inlet is pre-purified by the third filter before passing through the first filter. This prevents deterioration of the first filter and further reduces adhesion of bacteria and viruses to the fan and second filter disposed downstream of the first filter, thereby maintaining the hygienic state of the fan and second filter for a longer period of time.

[0022] According to a sixteenth aspect of the present disclosure, in the air conditioner of the fifteenth aspect, the sterilization unit may sterilize a space downstream of the third filter and upstream of the first filter in the direction of the airflow. In this case, air drawn in through the air intake port is purified by the third filter, then sterilized by the sterilization unit, and then purified again by the first filter. By guiding the purified air to the fan and the second filter, adhesion of bacteria and viruses to the fan and the second filter is further suppressed, and the hygienic state of the fan and the second filter can be maintained for a longer period of time.

[0023] According to a seventeenth aspect of the present disclosure, the air conditioner of any of the eleventh to sixteenth aspects further includes a rectifying member that rectifies the air flow from the air inlet to the fan, the rectifying member having a first portion and a second portion that is closer to the air inlet than the first portion and has a larger diameter than the first portion, and the first filter may be attached to the second portion. In this case, the area of ​​the first filter can be increased to match the diameter of the second portion of the rectifying member. This can reduce pressure loss in the first filter.

[0024] An eighteenth aspect of the present disclosure is the air conditioner of any one of the tenth to seventeenth aspects, wherein the sterilization section includes an active species generation section. In this case, a high sterilization effect can be obtained.

[0025] In the air conditioner according to any one of the tenth to eighteenth aspects, a nineteenth aspect of the present disclosure provides the air conditioner, wherein the second filter is a HEPA filter. In this case, a high sterilization effect is obtained.

[0026] According to a twentieth aspect of the present disclosure, in the air conditioner of any of the first to nineteenth aspects, the air conditioner further includes a control unit that controls the irradiation unit and a sensor that detects an ambient temperature of the irradiation unit, and the control unit may stop the irradiation of ultraviolet light by the irradiation unit when the ambient temperature is equal to or higher than a predetermined temperature. Continuing to irradiate ultraviolet light when the ambient temperature is high will cause the irradiation unit to deteriorate, but this aspect can mitigate this problem.

[0027] An air conditioner according to a twenty-first aspect of the present disclosure is a ceiling-mounted air conditioner according to any one of the first to fourteenth aspects, further including a third filter and a support member supporting the third filter, the support member being detachable from the casing, and the irradiation unit stopping irradiation of ultraviolet light when the support member is removed from the casing. In this case, irradiation of ultraviolet light is stopped in response to removal of the support member rather than the third filter. This reduces delays in switching irradiation on and off, and can prevent workers from being exposed to ultraviolet light irradiated from the irradiation unit.

[0028] According to a twenty-second aspect of the present disclosure, in the twenty-first aspect, the casing may have a contact portion, and when the support member comes into contact with the contact portion, ultraviolet light can be emitted by the irradiation portion. In this case, switching can be performed by a physical mechanism.

[0029] According to a twenty-third aspect of the present disclosure, in the twenty-second aspect, the support member may have a protrusion, and when the protrusion comes into contact with the contact portion, ultraviolet light can be emitted by the irradiation portion. In this case, switching can be performed by the protrusion provided on the support member.

[0030] According to a twenty-fourth aspect of the present disclosure, in the air conditioner of the twenty-third aspect, the support member may have an attachment portion at one end and be rotatable relative to the casing around the attachment portion, and the protrusion may be disposed at the other end of the support member. In this case, contact and separation between the protrusion and the contact portion occurs quickly when the support member is attached or detached, improving switching accuracy.

[0031] According to a twenty-fifth aspect of the present disclosure, in the air conditioner of the twenty-fourth aspect, the support member is rectangular, the casing has a rectangular opening covered by the support member, the opening has a first side along which the contact portion is arranged, a second side, a third side, and a fourth side, the second side, the third side, and the fourth side have attached portions corresponding to the attaching portions, the support member has a fifth side constituting the one end and a sixth side, a seventh side, and an eighth side constituting the other end, and the protrusions are arranged on the sixth side, the seventh side, and the eighth side. In this case, the attaching portion of the support member can be attached to any of three of the four sides of the opening (the second side, the third side, and the fourth side) excluding the side along which the contact portion is arranged (the first side). Furthermore, by providing protrusions on three of the four sides of the support member (the sixth, seventh, and eighth sides), excluding the side (the fifth side) on which the attachment portion is provided, contact and separation between the protrusions and the contact portion is achieved when attaching or detaching the support member, regardless of whether the attachment portion is located on the second, third, or fourth side of the opening, and switching can be performed reliably. In other words, it is possible to achieve both improved flexibility in attaching the support member and the ability to perform switching.

[0032] In an air conditioner according to a twenty-sixth aspect of the present disclosure, in any one of the twenty-third to twenty-fifth aspects, the support member may have a first region that supports the third filter and a second region outside the first region, and the protrusion may be disposed in the second region. In this case, interference between the third filter and the protrusion can be suppressed. Consequently, a decrease in switching accuracy due to interference between the third filter and the protrusion can be suppressed.

[0033] In the air conditioner according to a twenty-seventh aspect of the present disclosure, in any one of the twenty-third to twenty-sixth aspects, the contact portion may be larger in size than the protrusion. In this case, even if an error occurs in the positional relationship between the protrusion and the contact portion due to a manufacturing error or an assembly error of the protrusion, the protrusion can reliably contact the contact portion, thereby ensuring reliable switching.

[0034] The air conditioner according to a twenty-eighth aspect of the present disclosure is the air conditioner of any of the twentieth to twenty-seventh aspects, and may further include a notification unit that notifies the operator that ultraviolet radiation by the radiation unit has stopped. In this case, the operator can access the interior of the casing and perform maintenance work inside the casing after confirming the notification from the notification unit. This can more reliably prevent the operator from being exposed to ultraviolet radiation.

[0035] 1 is a plan view of an air conditioner according to a first embodiment of the present disclosure, as viewed from below. It is a cross-sectional view taken along line II-II of the air conditioner shown in FIG. 1. It is a partial cross-sectional view taken along line III-III of the air conditioner shown in FIG. 1, and a partially enlarged view thereof. It is a perspective view of the air conditioner shown in FIG. 1 from below, with the intake grille and decorative panel removed. It is a schematic diagram showing the positional relationship between the ultraviolet ray irradiation unit, the UVC emitted therefrom, and the coarse dust filter in the air conditioner shown in FIG. 1. It is a cross-sectional view corresponding to FIG. 2, showing the state in which the intake grille has been rotated to open the opening of the casing in the air conditioner shown in FIG. 1. It is a perspective view corresponding to FIG. 6. It is a schematic view showing the state in which the opening of the casing is closed by the intake grille, and the protrusion of the intake grille is in contact with the contact member of the limit switch provided on the casing in the air conditioner shown in FIG. 1. It is a schematic view showing the state in which the intake grille has been removed from the casing, and the protrusion of the intake grille is separated from the contact member of the limit switch provided on the casing in the air conditioner shown in FIG. 1. It is a block diagram showing the electrical configuration of the air conditioner shown in FIG. 1. Fig. 1 is a schematic diagram showing the positional relationship between an ultraviolet ray irradiation unit, ultraviolet rays irradiated therefrom, and a coarse dust filter in an air conditioner according to a second embodiment of the present disclosure; Fig. 2 is a schematic diagram showing the positional relationship between an ultraviolet ray irradiation unit, ultraviolet rays irradiated therefrom, and a coarse dust filter in an air conditioner according to a third embodiment of the present disclosure; Fig. 3 is a schematic diagram showing the positional relationship between an ultraviolet ray irradiation unit, ultraviolet rays irradiated therefrom, and a coarse dust filter in an air conditioner according to a fourth embodiment of the present disclosure.

[0036] (First embodiment) <Overall configuration of air conditioner> First, the overall configuration of an air conditioner 1 according to a first embodiment of the present disclosure will be described with reference to Figures 1 and 2. In the following description, directions such as "up," "down," "vertical," and "horizontal" refer to directions when the air conditioner 1 is installed in the state shown in Figure 2.

[0037] The air conditioner 1 comprises a casing 10, an intake grill 20, a decorative panel 25, a fan 30, a straightening member 40, four filter units 50, a coarse dust filter 60, a pre-filter 70, a sterilization section 90, and a control section 100.

[0038] The air conditioner 1 is a ceiling-mounted air conditioner in which a casing 10 is embedded in a ceiling C.

[0039] The fan 30, the straightening member 40, the four filter units 50, the coarse dust filter 60, the pre-filter 70, and the sterilization section 90 are disposed within the casing 10. The control section 100 is fixed to the outer surface of the casing 10.

[0040] The casing 10 is a rectangular cylindrical member with a bottom, and has a rectangular opening 10x on the bottom surface. The intake grille 20 and the decorative panel 25 are attached to the bottom surface of the casing 10. The intake grille 20 and the decorative panel 25 are arranged along the ceiling surface C1.

[0041] The intake grille 20 corresponds to the "support member" in the present disclosure. The intake grille 20 is a rectangular plate member that covers the opening 10x on the underside of the casing 10. The intake grille 20 has a protrusion 20z at one end. The protrusion 20z corresponds to the "mounting portion" in the present disclosure. The protrusion 20z extends horizontally along one of the four sides of the rectangular intake grille 20. The casing 10 has a recess 10z, which corresponds to the "mounted portion" in the present disclosure, on the periphery of the opening 10x. The intake grille 20 is supported on the casing 10 so as to be rotatable about the protrusion 20z with the protrusion 20z positioned within the recess 10z. The intake grille 20 rotates about the protrusion 20z relative to the casing 10 to open and close the opening 10x. In other words, by rotating the intake grille 20 relative to the casing 10, the opening 10x can be closed as shown in Figure 2 or opened as shown in Figures 6 and 7. The intake grille 20 is detachable from the casing 10.

[0042] The intake grille 20 has a central region 20r1 in which the intake port 11, which is composed of a plurality of through-holes 11x, is formed, and an edge region 20r2 outside the central region 20r1. The intake port 11 is rectangular. The central region 20r1 corresponds to the "first region" in this disclosure. The edge region 20r2 corresponds to the "second region" in this disclosure. The protrusion 20z is provided in the edge region 20r2.

[0043] The decorative panel 25 is formed along the periphery of the intake grille 20 and has four straight line portions corresponding to the four sides of the intake grille 20. A flap 25f is provided on each straight line portion of the decorative panel 25. The flap 25f is rotatably supported with respect to the decorative panel 25. The flap 25f rotates with respect to the decorative panel to open and close the air outlet 12. In other words, the rotation of the flap 25f with respect to the decorative panel can establish a closed state of the air outlet 12 as shown in FIG. 1 and an open state of the air outlet 12 as shown in FIG. 2.

[0044] In this way, the air inlet 11 and the air outlet 12 are arranged on the lower surface of the casing 10 .

[0045] The fan 30 is a centrifugal fan and includes a motor 31 and a plurality of fins 32. When the fan 30 is driven by the motor 31 to rotate the fins 32, it generates an airflow that flows from the air intake 11, passes through the pre-filter 70 and the coarse dust filter 60, passes through the air straightening member 40 and the fan 30, and heads toward the filter unit 50 and the air outlet 12, as shown by the thick arrow in Fig. 2 .

[0046] The fan 30 is disposed above the air inlet 11. The fan 30 faces the air inlet 11 and overlaps with the air inlet 11 in the vertical direction.

[0047] The rectifying member 40 is a cylindrical member that forms an air passage from the suction port 11 to the fan 30, and rectifies the air from the suction port 11 to the fan 30. The rectifying member 40 overlaps with the suction port 11 in the vertical direction, and is disposed above the suction port 11 and below the fan 30.

[0048] The flow straightening member 40 has an upper portion 41 having a generally truncated cone shape and a lower portion 42 having a rectangular cylindrical shape. The upper portion 41 corresponds to the "first portion" in this disclosure, and the lower portion 42 corresponds to the "second portion" in this disclosure. The upper end 41a of the upper portion 41 overlaps horizontally with the lower end 32b of the fin 32. The lower portion 42 is closer to the suction port 11 than the upper portion 41 and has a larger diameter than the upper end 41a of the upper portion 41. The upper end 41a of the upper portion 41 corresponds to the upper end 40a of the flow straightening member 40, and the lower end 42b of the lower portion 42 corresponds to the lower end 40b of the flow straightening member 40.

[0049] The four filter units 50 are disposed above the air inlet 11 and to the sides of the fan 30. The four filter units 50 are disposed along the circumference of the fan 30 at positions facing the four side surfaces of the casing 10, respectively.

[0050] Each filter unit 50 has a HEPA filter (High Efficiency Particulate Air Filter) 51, a deodorizing filter 52, and a filter frame 55. The filter frame 55 supports the HEPA filter 51 and the deodorizing filter 52 and is detachable from the casing 10. The HEPA filter 51 corresponds to the "second filter" in this disclosure.

[0051] The HEPA filter 51 and the deodorizing filter 52 are stacked in the direction of the airflow. The deodorizing filter 52 is located downstream of the HEPA filter 51 in the direction of the airflow. The HEPA filter 51 has a pleated shape with peaks and valleys formed along the direction of the airflow. The deodorizing filter 52 adsorbs odorous components and reduces the odorous components from the room in which the air conditioner 1 is installed. The deodorizing filter 52 is made of, for example, activated carbon.

[0052] Each filter unit 50 is disposed so as to intersect with a vertical plane and a horizontal plane. In other words, each filter unit 50 is disposed at an angle. The surfaces of each filter 51, 52 intersect with the vertical and horizontal directions. In each filter unit 50, the lower end 50b is closer to the fan 30 in the horizontal direction than the upper end 50a and is located inside the casing 10. In each filter unit 50, the inner side is the upstream side in the airflow direction and faces the fan 30, and the outer side is the downstream side in the airflow direction and faces the side wall of the casing 10.

[0053] The lower end 55 b of the filter frame 55 corresponds to the lower end 50 b of the filter unit 50 , and the upper end 55 a of the filter frame 55 corresponds to the upper end 50 a of the filter unit 50 .

[0054] The lower end 50 b of each filter unit 50 is located higher than the lower end 40 b of the flow rectifying member 40 .

[0055] The coarse dust filter 60 is attached to the lower part 42 of the flow straightening member 40, and is disposed in a space downstream of the suction port 11 and upstream of the fan 30 in the direction of the airflow (between the suction port 11 and the fan 30). The coarse dust filter 60 is fixed to the flow straightening member 40 by an upper holder (not shown) disposed below the lower part 42 of the flow straightening member 40, and a lower holder 64 (see FIG. 4) disposed below the upper holder and sandwiching the coarse dust filter 60 between the upper holder and the lower holder. The coarse dust filter 60 corresponds to the "first filter" in this disclosure.

[0056] The coarse dust filter 60 is spaced apart in the vertical direction from the upper end 42 a of the lower portion 42 of the straightening member 40. This prevents the coarse dust filter 60 from interfering with the straightening effect of the straightening member 40.

[0057] The pre-filter 70 is supported on the upper surface of the central region 20r1 of the suction grille 20, and is disposed in a space downstream of the suction port 11 and upstream of the coarse dust filter 60 in the direction of the airflow (between the suction port 11 and the coarse dust filter 60). The pre-filter 70 covers the multiple through-holes 11x that make up the suction port 11. Air drawn in through the suction port 11 is purified by the pre-filter 70 and then supplied into the casing 10. The pre-filter 70 corresponds to the "third filter" of the present disclosure. The pre-filter 70 has lower rigidity than the suction grille 20.

[0058] The HEPA filter 51 has a collection efficiency of 99.97% or more for particles with a particle diameter of 0.3 μm or larger. The minimum particle size (particle diameter 0.3 μm) for which a predetermined collection efficiency (e.g., 99.97%) can be achieved by the HEPA filter 51 is smaller than the minimum particle size for which the coarse dust filter 60 can achieve the predetermined collection efficiency. The minimum particle size for which the prefilter 70 can achieve the predetermined collection efficiency is larger than the minimum particle size for which the coarse dust filter 60 can achieve the predetermined collection efficiency.

[0059] The sterilization unit 90 includes an irradiation unit 91 (see FIGS. 3 and 4) that irradiates ultraviolet rays and an active species generation unit 92 that generates active species, and sterilizes the space downstream of the air intake 11 and upstream of the fan 30 in the direction of the airflow inside the casing 10 (between the pre-filter 70 and the coarse dust filter 60). In the present disclosure, the sterilization of bacteria and the decomposition of odorous components and viruses using ultraviolet rays and active species are collectively referred to simply as "sterilization."

[0060] The irradiation unit 91 includes a UVC-LED (ultraviolet C-light emitting diode) 95 (see FIG. 3) that emits ultraviolet C rays (hereinafter referred to as "UVC") with a wavelength of 200 to 280 nanometers. The UVC-LED 95 irradiates UVC toward the space downstream of the suction port 11 and upstream of the coarse dust filter 60 in the direction of the airflow (between the suction port 11 and the coarse dust filter 60). While the HEPA filter 51 has a pleated shape, the coarse dust filter 60 is flat. Here, "flat" means that there are no creases (pleats) on the surface, and no shadows are created when light is irradiated obliquely onto the surface. With a pleated shape like the HEPA filter 51, UVC rays have difficulty reaching the deepest part. In contrast, the coarse dust filter 60 is flat, allowing UVC rays to easily reach the deepest part.

[0061] The active species generating unit 92 decomposes harmful substances, including odor components. The active species generating unit 92 has an inlet 92x and an outlet 92y. The inlet 92x is located in a space downstream of the deodorizing filter 52 and upstream of the outlet 12 in the direction of the airflow (between the deodorizing filter 52 and the outlet 12). The outlet 92y is located in a space downstream of the inlet 11 and upstream of the fan 30 in the direction of the airflow (between the pre-filter 70 and the coarse dust filter 60). Odor components remaining in the air that are not adsorbed by the deodorizing filter 52 are taken into the active species generating unit 92 through the inlet 92x before being blown out through the outlet 12, and are decomposed by the active species generating unit 92. The air from which harmful substances, including odor components, have been removed by the active species generating unit 92 is then supplied through the outlet 92y to between the pre-filter 70 and the coarse dust filter 60.

[0062] <Details of the Irradiation Unit> A passage P for the airflow is provided between the suction port 11 and the coarse dust filter 60. As shown in Figures 4 and 5, the passage P is formed by being surrounded by four sides S1, S2, S3, and S4. The surfaces of the four sides S1, S2, S3, and S4 are generally flat, although they have irregularities and openings, and in this embodiment, each of them will be described as being substantially flat. All of the four sides S1, S2, S3, and S4 are vertical surfaces. The four sides S1, S2, S3, and S4 are orthogonal to each other, and the horizontal cross section of the rectangular prism space surrounded by the four sides S1, S2, S3, and S4 is a square with corners C1, C2, C3, and C4, as can be seen from Figure 5.

[0063] The irradiation unit 91 is disposed on one of the four surfaces S1, S2, S3, and S4 except for the four corners corresponding to the corners C1, C2, C3, and C4, and irradiates UVC light toward the passage P. In this embodiment, the irradiation unit 91 is disposed on one of the four surfaces S1, S2, S3, and S4, S1, which is parallel to the outer surface of the casing 10 to which the control unit 100 is fixed, and is closest to the control unit 100, in a plan view. The irradiation unit 91 is disposed at a position Y (between the center X and the corner C1) that is neither at either end (the corners C1 and C2) nor at the center X in the direction connecting the ends of the surface S1. The irradiation unit 91 is positioned outside the area facing the coarse dust filter 60 in the vertical direction. In this embodiment, the vertical direction, the front-rear direction, and the left-right direction of the air conditioner 1 are defined as shown in FIGS. 3 and 5 .

[0064] As shown in FIG. 3 , the UVC LED 95 is supported on a slightly inclined substrate 94 so that its upper end is positioned further rearward than its lower end. The UVC LED 95 is electrically connected to the control unit 100. The UVC LED 95 is covered by a cap 96 that defines the angle of irradiation into the passage P. The UVC light passage surface 96a, which is the front surface of the cap 96, is slightly inclined so that its upper end is positioned further rearward than its lower end. In this embodiment, the UVC light irradiated from the UVC LED 95 and passing through the cap 96 spreads according to the light distribution defined by the cap 96. As can be seen from the enlarged view of FIG. 3 , the UVC light emission direction D is directed upward at an angle θ1 with respect to the horizontal in the vertical direction. In this embodiment, the light emission direction D is perpendicular to the UVC light passage surface 96a, which is the front surface of the cap 96.

[0065] As shown in FIG. 5 , which shows the coarse dust filter 60 viewed from below, UVC rays spread into the passage P at an obtuse angle θ2 from the irradiation unit 91 in a plan view. The line segment E1 indicates a direction that bisects the angle θ2. In this embodiment, the line segment E1 is perpendicular to the passage surface 96a, which is the front surface of the cap 96. The line segment E1 may or may not coincide with the direction of the intensity center of the UVC rays emitted from the irradiation unit 91. The length of the line segment E1 can be interpreted as representing the emission intensity of the UVC-LED 95. The irradiation unit 91 is disposed so that the passage surface 96a, which is the front surface of the cap 96, is inclined with respect to the surface S1. Specifically, in FIG. 5 , the irradiation unit 91 is inclined so that the left end of the passage surface 96a is closer to the surface S1 than the right end. Therefore, the line segment E1 is inclined at an acute angle θ3 with respect to the line segment connecting the center X of the surface S1 and the position Y. The line segment E1 passes between the center point O of the square coarse dust filter 60 and the surface S4 and heads toward the surface S3. The distance from the tip of the line segment E1 to the surface S3 is relatively small, but the distance from the tip of the line segment E1 to the corner C3 and the surface S2 is relatively large compared to the distance from the tip of the line segment E1 to the corner C4 and the surface S4.

[0066] A shielding member 97 that restricts the irradiation range of UVC is disposed in front of the irradiation unit 91. The shielding member 97 corresponds to the "member that restricts ultraviolet rays from traveling toward the air inlet 11" in this disclosure. The shielding member 97 has an upper surface 97a and a lower surface 97b that face the area through which UVC passes. The upper surface 97a, which is inclined so that it is positioned higher toward the front, blocks UVC traveling upward from the cap 96 and backward from the cap 96. The lower surface 97b is a horizontal surface with a protrusion at its tip. In this embodiment, the lower surface 97b is at the same height as the lower end of the UVC-LED 95. The lower surface 97b blocks UVC traveling downward from the cap 96. By providing the shielding member 97, the UVC light is not emitted toward the suction port 11, but passes through an irradiation area R (shown by hatching in FIG. 3 ) through which the UVC passes in the passage P, and is irradiated onto the lower surface of the coarse dust filter 60 at the upper end of the passage P, and onto three surfaces S2, S3, and S4 of the passage P other than the surface S1 on which the irradiation unit 91 is located. The lower end of the irradiation area R is sufficiently far from the suction port 11.

[0067] The UVC emitted from the irradiation unit 91 sterilizes the air in the irradiation area R and also sterilizes the coarse dust filter 60 to which bacteria, viruses, etc. are attached. As a result, the air that passes through the coarse dust filter 60, passes through the fan 30, the HEPA filter 51, and the deodorizing filter 52, and is blown out from the air outlet 12 is sterilized.

[0068] <Configuration of Intake Grille and Periphery of Opening> Next, the configuration of the intake grille 20 and the periphery of the opening 10x in the casing 10 will be described in detail.

[0069] As shown in FIG. 1 , the opening 10x has a first side 10x1, a second side 10x2, a third side 10x3, and a fourth side 10x4. The first side 10x1 and the second side 10x2 are parallel to each other. The third side 10x3 and the fourth side 10x4 are parallel to each other. The third side 10x3 connects one end of the first side 10x1 to one end of the second side 10x2 and is perpendicular to the first side 10x1 and the second side 10x2. The fourth side 10x4 connects the other end of the first side 10x1 to the other end of the second side 10x2 and is perpendicular to the first side 10x1 and the second side 10x2.

[0070] The intake grille 20 has a fifth side 20x5, a sixth side 20x6, a seventh side 20x7, and an eighth side 20x8. The fifth side 20x5 and the sixth side 20x6 are parallel to each other. The seventh side 20x7 and the eighth side 20x8 are parallel to each other. The seventh side 20x7 connects one end of the fifth side 20x5 to one end of the sixth side 20x6 and is perpendicular to the fifth side 20x5 and the sixth side 20x6. The eighth side 20x8 connects the other end of the fifth side 20x5 to the other end of the sixth side 20x6 and is perpendicular to the fifth side 20x5 and the sixth side 20x6.

[0071] The fifth side 20x5 forms one end of the suction grille 20. The sixth side 20x6 forms the other end of the suction grille 20.

[0072] As shown in Fig. 7, the convex portion 20z is provided along the fifth side 20x5. Of the four sides of the intake grille 20, protrusions 21 are provided at the longitudinal centers of three sides (sixth side 20x6, seventh side 20x7, and eighth side 20x8) excluding the fifth side 20x5 on which the convex portion 20z is provided. The protrusions 21 are arranged in the edge region 20r2 (see Fig. 2).

[0073] A limit switch 200 is provided at the longitudinal center of the first side 10x1 around the periphery of the opening 10x of the casing 10. As will be described in detail later, the limit switch 200 operates in response to the opening and closing of the opening 10x, and switches between emitting UVC light by the UVC-LED 95 (see FIG. 3) and stopping UVC irradiation.

[0074] Of the four sides of opening 10x, recesses 10z corresponding to protrusions 20z are provided on three sides (second side 10x2, third side 10x3, and fourth side 10x4) excluding first side 10x1 on which limit switch 200 is arranged. Therefore, although intake grill 20 is attached so that fifth side 20x5 corresponds to second side 10x2 in Fig. 7, intake grill 20 can also be attached so that fifth side 20x5 corresponds to third side 10x3 or fourth side 10x4.

[0075] Next, the operation of the limit switch 200 in conjunction with the opening and closing of the opening 10x will be described.

[0076] As shown in Figures 8 and 9, the limit switch 200 includes a contact member 210 and a movable spring 220 provided on the side of the contact member 210. The contact member 210 is urged downward by a spring 230. The movable spring 220 is rotatable about an axis 220z provided at the base end, and is urged counterclockwise in Figures 8 and 9. The contact member 210 corresponds to the "contact portion" of the present disclosure, and is larger in size than the protrusion 21.

[0077] When the intake grille 20 is attached to the casing 10 and the opening 10x is closed by the intake grille 20, of the protrusions 21 provided on the three sides (sixth side 20x6, seventh side 20x7, and eighth side 20x8) of the intake grille 20, the protrusion 21 provided on the sixth side 20x6 comes into contact with the contact member 210 of the limit switch 200, as shown in FIG. 8 , and presses the contact member 210 upward against the biasing force of the spring 230. At this time, the movable spring 220 is held in a position resisting the biasing force in the counterclockwise direction by the pressure of the contact member 210, and closes the circuit of the limit switch 200. When the circuit of the limit switch 200 is closed, UVC irradiation by the UVC-LED 95 becomes possible.

[0078] When the intake grille 20 rotates around the protrusion 20z relative to the casing 10 and the opening 10x is opened (see FIGS. 6 and 7), the protrusion 21 provided on the sixth side 20x6 of the intake grille 20 moves away from the contact member 210 of the limit switch 200, as shown in FIG. 9. As a result, the contact member 210 moves downward due to the biasing force of the spring 230, and the movable spring 220 rotates counterclockwise in FIG. 9 around the axis 220z, thereby opening the circuit of the limit switch 200. When the circuit of the limit switch 200 is open, UVC radiation from the UVC-LED 95 is stopped.

[0079] When the suction grille 20 is attached to the casing 10 from a state in which the opening 10x is open and the suction grille 20 closes the opening 10x, the protrusion 21 provided on the sixth side 20x6 of the suction grille 20 comes into contact with the contact member 210 of the limit switch 200, as shown in FIG. 8, and presses the contact member 210 upward against the biasing force of the spring 230. Accordingly, the contact member 210 moves upward, and the movable spring 220 rotates clockwise in FIG. 8 around the axis 220z, thereby closing the circuit of the limit switch 200. Closing the circuit of the limit switch 200 enables UVC irradiation by the UVC-LED 95.

[0080] 10 , the control unit 100 is composed of a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, etc., and controls the fan 30, the sterilization unit 90, and the alarm unit 110. The control unit 100 is electrically connected to the motor 31 of the fan 30, the UVC-LED 95 of the irradiation unit 91 in the sterilization unit 90, the active species generation unit 92 in the sterilization unit 90, the alarm unit 110, and the sensor 120.

[0081] The notification unit 110 is composed of a display unit that displays images, an audio output unit that outputs audio, a light-emitting unit (LED: light emitting diode) that emits light, etc. The display unit may be provided in the air conditioner 1 and / or a remote controller attached to the air conditioner 1. When the opening 10x is opened and the UVC-LED 95 is turned off, the control unit 100 causes the notification unit 110 to notify the user of the stop of UVC irradiation by the UVC-LED 95 through images, audio, and / or light. For example, under the control of the control unit 100, the light-emitting unit that constitutes the notification unit 110 lights up when the opening 10x is closed and turns off when the opening 10x is opened.

[0082] The sensor 120 detects the ambient temperature of the irradiation unit 91. The sensor 120 is composed of a thermistor or the like, and is provided in the air conditioner 1 and / or a remote controller attached to the air conditioner 1. The sensor 120 detects the temperature near the air inlet 11 and / or the temperature of the room in which the air conditioner 1 is installed as the ambient temperature of the irradiation unit 91, and outputs a signal indicating that temperature to the control unit 100. The control unit 100 receives the signal from the sensor 120, and when it determines that the ambient temperature of the irradiation unit 91 is equal to or higher than a predetermined temperature, it stops the irradiation of ultraviolet rays by the irradiation unit 91.

[0083] Note that the intake grille 20 is not an electrical element in Figure 10, but is shown for illustrative purposes. The limit switch 200 is connected to a power supply circuit that supplies power to the UVC-LEDs 95 of the irradiation unit 91. When the intake grille 20 comes into contact with the limit switch 200 and the circuit of the limit switch 200 is closed, power is supplied from the power supply circuit to the UVC-LEDs 95 of the irradiation unit 91 (see the solid arrow in Figure 10). At this time, UVC irradiation by the UVC-LEDs 95 becomes possible. When the intake grille 20 moves away from the limit switch 200 and the circuit of the limit switch 200 is opened, the power supply from the power supply circuit to the UVC-LEDs 95 of the irradiation unit 91 is cut off (see the dashed arrow in Figure 10). At this time, UVC is not emitted from the UVC-LEDs 95.

[0084] Effect of First Embodiment As described above, the irradiation unit 91 irradiates UVC light toward the passage P, which is a space downstream of the suction port 11 and upstream of the coarse-dust filter 60 in the direction of the airflow. In this embodiment, it is possible to sterilize the air passing through the passage P and the coarse-dust filter 60 using only one irradiation unit 91. Since sterilization is possible with a small number of irradiation units 91, the number of parts can be reduced and the size of the casing 10 can be kept from increasing. Therefore, it is possible to achieve a low cost for the air conditioner 1. Furthermore, in this embodiment, because the number of suction ports 11 is fewer than the number of outlets 12, the structure of the passage for the airflow from the suction port to the coarse-dust filter 60 can be simplified compared to when the number of suction ports 11 is equal to or greater than the number of outlets 12.

[0085] The air conditioner 1 is a ceiling-mounted type, which can enhance the sterilization effect of the air near the ceiling.

[0086] The emission direction D of the UVC emitted from the irradiation unit 91 is directed vertically upward from the horizontal (see FIG. 3 ). In this case, leakage of UVC to the outside from the suction port 11 can be suppressed. This in turn can suppress exposure of workers performing maintenance work inside the casing 10 to UVC.

[0087] The irradiation unit 91 is disposed on one of the four sides S1, S2, S3, and S4 constituting the passage P except for the four corners corresponding to the corners C1, C2, C3, and C4, and irradiates UVC light toward the inside of the passage P (see FIGS. 4 and 5). In this case, the area where the ultraviolet light intensity is weak can be made small.

[0088] The irradiation unit 91 irradiates the passage P, which is a space upstream of the coarse dust filter 60 in the direction of the airflow, with UVC light. This makes it possible to sterilize the coarse dust filter 60 and the air passing through the coarse dust filter 60.

[0089] A shielding member 97 is provided to restrict the UVC emitted from the irradiation unit 91 from heading toward the air inlet 11. This prevents the UVC emitted from the irradiation unit 91 from leaking to the outside through the air inlet 11.

[0090] The irradiation unit 91 includes a UVC-LED 95. In this case, the UVC-LED 95 irradiates UVC light, which is in a wavelength range that has a high sterilization effect, and therefore the sterilization effect can be enhanced.

[0091] The UVC irradiation intensity on the surface of the coarse-dust filter 60 attenuates inversely with the square of the distance from the UVC-LED 95 to the irradiation point, and also attenuates in proportion to the cosine (cos θ4) of the incident angle θ4 of the UVC onto the coarse-dust filter 60. The incident angle θ4 is the angle between the incident light and the normal to the surface, and an example is shown in FIG. 3 . Since the incident angle θ4 increases the farther the irradiation point is from the irradiation unit 91, the UVC irradiation intensity decreases the farther the irradiation point is from the UVC-LED 95. To achieve a sufficient sterilization effect on the coarse-dust filter 60, it is desirable that the irradiation intensity at the irradiation point be equal to or greater than a certain value. However, because there is an upper limit to the emission intensity of the UVC-LED 95, it may be possible that the UVC irradiated from a single UVC-LED 95 cannot irradiate the entire surface of the coarse-dust filter 60 with an irradiation intensity equal to or greater than a certain value.

[0092] In this embodiment, the irradiation unit 91 is positioned so that UVC radiation is irradiated toward the passage P from a position Y that is neither the center X nor either end in the direction connecting the ends of the surface S1, and the line segment E1 is inclined so as to form an acute angle θ3 with respect to the line segment connecting the center X and the position Y, thereby reducing the area where the irradiation intensity is below a certain value. Specifically, in FIG. 5 , the area F1 on the surface of the coarse-dust filter 60 near the corner C3, which is the boundary between the surfaces S2 and S3, is far from the irradiation unit 91, so the UVC irradiation intensity is below a certain value, but the area is relatively small. Furthermore, the area F2 on the surface of the coarse-dust filter 60 near the corner C1, which is the boundary between the surfaces S1 and S4, is outside the range of the angle θ2, so the UVC irradiation intensity is below a certain value, but the area is relatively small. To address the risk of insufficient sterilization of regions F1 and F2 of the coarse dust filter 60, a member for blocking these two regions F1 and F2 may be provided to make regions F1 and F2 non-passable regions. In this embodiment, as shown in FIG. 4 , the lower holder 64 includes a plate 64a having dimensions capable of blocking region F2. The plate 64a is integrally formed with the square outer frame that is the main body of the lower holder 64. By covering the surface of region F2, region F2 becomes a non-passable region for air. Although not shown, the lower holder 64 also includes a plate having dimensions capable of blocking region F1. The total area of ​​regions F1 and F2 is smaller than the area of ​​region F3 described in the second embodiment and the total area of ​​regions F4, F5, F6, and F7 described in the third embodiment.

[0093] The air conditioner 1 includes a HEPA filter 51 located downstream of the fan 30 in the direction of the airflow within the casing 10, and a sterilization unit 90 located within the casing 10 for sterilizing the space downstream of the air inlet 11 and upstream of the fan 30 in the direction of the airflow. In this case, air drawn in through the air inlet 11 is sterilized by the sterilization unit 90 and then guided to the fan 30 and the HEPA filter 51 (see FIG. 2). This prevents bacteria and viruses from adhering to the fan 30 and the HEPA filter 51, thereby maintaining the hygienic state of the fan 30 and the HEPA filter 51.

[0094] The air conditioner 1 further includes a coarse dust filter 60 located downstream of the air inlet 11 and upstream of the fan 30 in the direction of the airflow within the casing 10 (see FIG. 2). In this case, the air drawn in through the air inlet 11 is purified in advance by the coarse dust filter 60 before being guided to the fan 30 and HEPA filter 51. This prevents deterioration of the HEPA filter 51. Furthermore, adhesion of bacteria and viruses to the fan 30 and HEPA filter 51 is further prevented, allowing the hygienic state of the fan 30 and HEPA filter 51 to be maintained for a longer period of time.

[0095] The minimum particle size at which the HEPA filter 51 can achieve a predetermined collection efficiency (e.g., 99.97%) is smaller than the minimum particle size at which the coarse dust filter 60 can achieve the predetermined collection efficiency. In this case, relatively large particles are captured by the coarse dust filter 60, which can prevent clogging of the HEPA filter 51. Furthermore, by capturing relatively small particles with the HEPA filter 51, the collection performance of the air conditioner 1 as a whole is improved.

[0096] The sterilization unit 90 includes an irradiation unit 91 that irradiates ultraviolet light (see FIG. 2). In this case, a high sterilization effect can be obtained.

[0097] The irradiation unit 91 irradiates ultraviolet light toward the coarse dust filter 60 (see FIGS. 2 and 3). In this case, bacteria and viruses adhering to the coarse dust filter 60 are removed by irradiation with ultraviolet light, thereby preventing a decrease in the sterilization ability of the coarse dust filter 60. Furthermore, adhesion of bacteria and viruses to the fan 30 and HEPA filter 51, which are arranged downstream of the coarse dust filter 60, is further prevented, allowing the hygienic state of the fan 30 and HEPA filter 51 to be maintained for a longer period of time.

[0098] The minimum particle size at which the pre-filter 70 achieves a predetermined collection efficiency (e.g., 99.97%) is larger than the minimum particle size at which the coarse dust filter 60 achieves the predetermined collection efficiency. In this case, the air drawn in through the air inlet 11 is pre-cleaned by the pre-filter 70 and then passes through the coarse dust filter 60. This prevents deterioration of the coarse dust filter 60 and further suppresses adhesion of bacteria and viruses to the fan 30 and HEPA filter 51 located downstream of the coarse dust filter 60, thereby maintaining the hygienic state of the fan 30 and HEPA filter 51 for a longer period of time. Furthermore, by capturing relatively large particles using the pre-filter 70 and then capturing particles smaller than those captured by the pre-filter 70 using the coarse dust filter 60, the collection performance of the air conditioner 1 as a whole is improved.

[0099] The sterilization unit 90 sterilizes the space downstream of the pre-filter 70 and upstream of the coarse dust filter 60 in the direction of the airflow (see FIG. 2). In this case, the air drawn in through the suction port 11 is purified by the pre-filter 70, then sterilized by the sterilization unit 90, and then further purified by the coarse dust filter 60. By directing the purified air to the fan 30 and the HEPA filter 51, adhesion of bacteria and viruses to the fan 30 and the HEPA filter 51 is further suppressed, and the hygienic state of the fan 30 and the HEPA filter 51 can be maintained for a longer period of time.

[0100] The coarse dust filter 60 is attached to the lower part 42 of the flow straightening member 40 (see FIG. 2). In this case, the area of ​​the coarse dust filter 60 can be increased to match the diameter of the lower part 42 of the flow straightening member 40. This makes it possible to reduce pressure loss in the coarse dust filter 60.

[0101] The sterilization section 90 includes an active species generation section 92 (see FIG. 2). In this case, a high sterilization effect can be obtained.

[0102] The second filter of the present disclosure is a HEPA filter 51. In this case, a high sterilization effect can be obtained.

[0103] When the ambient temperature of the irradiation unit 91 is equal to or higher than a predetermined temperature, the control unit 100 stops the irradiation of ultraviolet rays by the irradiation unit 91. If the irradiation of ultraviolet rays continues when the ambient temperature is high, the irradiation unit 91 will deteriorate, but this embodiment can suppress this problem.

[0104] When the intake grille 20 is removed from the casing 10, the UVC-LEDs 95 of the irradiation unit 91 stop emitting UVC light (see FIGS. 6, 7, and 9). Because UVC light emission stops in response to the removal of the intake grille 20, rather than the pre-filter 70, delays in switching the irradiation on and off are unlikely to occur. Therefore, in a configuration in which the irradiation unit 91 is disposed inside the casing 10, workers can be prevented from being exposed to UVC light emitted from the irradiation unit 91.

[0105] When the protrusion 21 of the intake grille 20 comes into contact with the contact member 210 of the limit switch 200 provided on the casing 10, UVC irradiation by the irradiation unit 91 becomes possible (see FIG. 8). In this case, switching can be performed by a physical mechanism.

[0106] The intake grille 20 is rotatable relative to the casing 10 around a protrusion 20z provided at one end (see FIG. 7). The protrusion 21 is disposed at the other end of the intake grille 20 opposite the end at which the protrusion 20z is provided. In this case, when the intake grille 20 is attached or detached, the protrusion 21 and the contact member 210 come into contact with and separate from each other quickly, improving the accuracy of switching.

[0107] A limit switch 200 is disposed on a first side 10x1 of the opening 10x (see FIG. 5). Recesses 10z corresponding to the protrusions 20z are provided on a second side 10x2, a third side 10x3, and a fourth side 10x4 of the opening 10x. A protrusion 20z is provided on a fifth side 20x5 of the intake grille 20. Protrusions 21 are disposed on a sixth side 20x6, a seventh side 20x7, and an eighth side 20x8 of the intake grille 20. In this case, the protrusions 20z of the intake grille 20 can be attached to any of three of the four sides of the opening 10x (the second side 10x2, the third side 10x3, and the fourth side 10x4) except for the first side 10x1 on which the limit switch 200 is disposed. Furthermore, by providing protrusions 21 on three of the four sides of intake grille 20 (sixth side 20x6, seventh side 20x7, and eighth side 20x8), excluding fifth side 20x5 on which protrusion 20z is provided, contact and separation between protrusions 21 and contact member 210 is achieved when attaching or detaching intake grille 20, ensuring reliable switching. In other words, improved flexibility in attachment of intake grille 20 and easy switching can both be achieved.

[0108] The protrusions 21 are arranged in an edge region 20r2 (see FIG. 2) of the intake grille 20 (a region outside the central region 20r1 where the pre-filter 70 is supported). In this case, interference between the pre-filter 70 and the protrusions 21 can be suppressed. Consequently, a decrease in switching accuracy due to interference between the pre-filter 70 and the protrusions 21 can be suppressed.

[0109] The contact member 210 is larger in size than the protrusion 21 (see FIGS. 8 and 9). In this case, even if an error occurs in the positional relationship between the protrusion 21 and the contact member 210 due to a manufacturing error or an assembly error of the protrusion 21, the large size of the contact member 210 allows the protrusion 21 to reliably contact the contact member 210, thereby ensuring reliable switching.

[0110] The air conditioner 1 further includes a notification unit 110 that notifies the user that UVC irradiation by the irradiation unit 91 has stopped (see FIG. 10 ). In this case, after confirming the notification by the notification unit 110, the worker can access the inside of the casing 10 and perform maintenance work inside the casing 10 (for example, replacing the filter unit 50). This more reliably prevents the worker from being exposed to UVC.

[0111] Second Embodiment Next, an air conditioner according to a second embodiment of the present disclosure will be described with further reference to Fig. 6. The air conditioner according to this embodiment is the same as the first embodiment except for the position and irradiation range of the irradiation unit 91. Therefore, the following mainly describes the differences from the first embodiment.

[0112] As shown in FIG. 6 , in this embodiment, the irradiation unit 91 is disposed near one of the four corners C1 where the above-described surfaces S1 and S4 are connected. The irradiation unit 91 irradiates UVC light from the corner C1 toward the passage P. The UVC-LED is located outside the passage P and does not face the coarse dust filter 60 in the vertical direction. In a plan view, the UVC light spreads into the passage P at an angle θ5 from the irradiation unit 91. The angle θ5 is slightly greater than 90°. The direction bisecting the angle θ5 is indicated by line segment E2. In FIG. 6 , the length of line segment E2 is the same as the length of line segment E1 in FIG. 5 . In this embodiment, line segment E2 is perpendicular to the above-described passage plane 96a. Line segment E2 may or may not coincide with the direction of the intensity center of the UVC light irradiated from the irradiation unit 91. The irradiation unit 91 is disposed so that the passing surface 96a is inclined at 45° with respect to both the surface S1 and the surface S4. The line segment E2 is inclined at 45° with respect to both the surface S1 and the surface S4. The line segment E2 passes through the center point O of the coarse dust filter 60.

[0113] In this embodiment, as in the first embodiment, it is possible to sterilize the air passing through the passage P and the coarse dust filter 60 using only one irradiation unit 91. Since sterilization is possible with a small number of irradiation units 91 in this way, it is possible to reduce the number of parts and also to prevent the casing 10 from becoming larger.

[0114] In this embodiment, the irradiation unit 91 is positioned so that UVC is irradiated from the corner C1 toward the inside of the passage P, so the angle θ5 that defines the UVC irradiation range in a plan view can be made smaller than in the first embodiment and the third and fourth embodiments described below. Therefore, the UVC irradiation intensity can be increased at positions relatively close to the irradiation unit 91, thereby improving the sterilization effect. In addition, this embodiment can also achieve at least some of the effects described in the first embodiment.

[0115] On the other hand, in this embodiment, the area where the irradiation intensity is less than a certain value is larger than in the first embodiment and the third and fourth embodiments described later. In Fig. 6, in area F3 on the surface of the coarse-dust filter 60 near corner C3, which is the boundary between surface S2 and surface S3, the UVC irradiation intensity is less than a certain value because the area is far from the irradiation unit 91. The area of ​​area F3 is larger than the area of ​​area F1 described in Fig. 5.

[0116] Third Embodiment Next, an air conditioner according to a third embodiment of the present disclosure will be described with further reference to Fig. 7. The air conditioner according to this embodiment is the same as the first embodiment except for the position and irradiation range of the irradiation unit 91. Therefore, the following mainly describes the differences from the first embodiment.

[0117] As shown in FIG. 7 , in this embodiment, the irradiation unit 91 is disposed near the center X of the plane S1 in a plan view. The irradiation unit 91 irradiates UVC light from the center X toward the passage P. The UVC LED is located outside the passage P and does not face the coarse dust filter 60 in the vertical direction. The UVC light spreads into the passage P at an angle θ6 from the irradiation unit 91 in a plan view. The angle θ6 is greater than the angle θ2. The direction bisecting the angle θ6 is indicated by the line segment E3. In FIG. 7 , the length of the line segment E3 is the same as the length of the line segment E1 in FIG. 5 . In this embodiment, the line segment E3 is perpendicular to the above-described passage plane 96a. The line segment E3 may or may not coincide with the direction of the intensity center of the UVC light irradiated from the irradiation unit 91. The irradiation unit 91 is disposed so that the passage plane 96a is parallel to the plane S1. The line segment E3 is perpendicular to the plane S1. The line segment E3 passes through the center point O of the coarse dust filter 60. The distance from the tip of the line segment E3 to the surface S3 is relatively small, but the distance from the tip of the line segment E3 to the corners C3 and C4 is relatively large.

[0118] In this embodiment, as in the first embodiment, it is possible to sterilize the air passing through the passage P and the coarse dust filter 60 using only one irradiation unit 91. Since sterilization is possible with a small number of irradiation units 91 in this way, it is possible to reduce the number of parts and also to prevent the casing 10 from becoming larger.

[0119] In this embodiment, the irradiation unit 91 is positioned so that UVC light is irradiated from the center X of the direction connecting both ends of the surface S1 toward the passage P, thereby reducing the area where the irradiation intensity is less than a certain value. Specifically, in FIG. 7 , in areas F4 and F5 on the surface of the coarse-dust filter 60 near the corner C3 at the boundary between the surfaces S2 and S3 and near the corner C4 at the boundary between the surfaces S3 and S4, the UVC irradiation intensity is less than a certain value due to the large distance from the irradiation unit 91, but the area is relatively small. Furthermore, in areas F6 and F7 on the surface of the coarse-dust filter 60 near the corner C1 at the boundary between the surfaces S1 and S4 and near the corner C2 at the boundary between the surfaces S1 and S2, although they are within the range of angle θ6, they are near the boundary of this range, so the amount of light distribution is smaller than in the direction of the line segment E3, and the distance from the irradiation unit 91 is also large. Therefore, although the UVC irradiation intensity is less than a certain value, the area is relatively small. In addition, in this embodiment, at least some of the effects described in the first embodiment can be obtained.

[0120] (Fourth embodiment) Next, an air conditioner according to a fourth embodiment of the present disclosure will be described with further reference to Fig. 8. The air conditioner according to this embodiment is the same as the first embodiment except that it has two irradiation units. Therefore, the following mainly describes the differences from the first embodiment.

[0121] As shown in FIG. 8 , the air conditioner according to this embodiment includes an irradiation unit 91A that irradiates UVC light into the passage P from a position YA that is neither at either end (corner C1, C2) of surface S1 nor at the center XA in the direction connecting the ends of surface S1, and an irradiation unit 91B that irradiates UVC light into the passage P from a position YB that is neither at either end (corner C3, C4) of surface S3 opposite surface S1 nor at the center XB in the direction connecting the ends of surface S3. The irradiation unit 91A is located in the same position as the irradiation unit 91 described in the first embodiment, and the angle of inclination of the passage surface 96a relative to surface S1 is also the same. The irradiation unit 91A corresponds to the “first irradiation unit” in this disclosure. The irradiation unit 91B corresponds to the “second irradiation unit” in this disclosure.

[0122] In a plan view, the irradiation units 91A and 91B are arranged point-symmetrically with respect to the center point O of the coarse dust filter 60. In detail, in a plan view, the UVC spreads into the passage P from the irradiation unit 91A at an obtuse angle θ2A. A line segment E1A indicates a direction that bisects the angle θ2A. The line segment E1A is inclined at an acute angle θ3A with respect to the line segment connecting the center XA and the position YA. Similarly, in a plan view, the UVC spreads into the passage P from the irradiation unit 91B at an obtuse angle θ2B. A line segment E1B indicates a direction that bisects the angle θ2B. The line segment E1B is inclined at an acute angle θ3B with respect to the line segment connecting the center XB and the position YB. The angle θ2A is the same as the angle θ2B. The angle θ3A is the same as the angle θ3B. The distance from corner C1 to position YA is the same as the distance from corner C3 to position YB.

[0123] In this embodiment, two irradiation units 91A and 91B are used to sterilize the air passing through the passage P and the coarse dust filter 60. Since sterilization is possible with a small number of irradiation units 91A and 91B in this manner, the number of parts can be reduced and the size of the casing 10 can be prevented from increasing.

[0124] Furthermore, in this embodiment, because two irradiation units 91A and 91B are used, the area where the irradiation intensity is below a certain value can be made smaller than in the first embodiment. Specifically, in FIG. 8 , in area F2A on the surface of the coarse-dust filter 60 near corner C1, which is the boundary between surfaces S1 and S4, the UVC irradiation intensity is below a certain value because it is outside the range of UVC angle θ2A from the irradiation unit 91A and is far from the irradiation unit 91B, but the area is relatively small. Similarly, in area F2B on the surface of the coarse-dust filter 60 near corner C3, which is the boundary between surfaces S2 and S3, the UVC irradiation intensity is below a certain value because it is outside the range of UVC angle θ2B from the irradiation unit 91B and is far from the irradiation unit 91A, but the area is relatively small. The sum of the areas of areas F2A and F2B is smaller than the sum of the areas of areas F1 and F2 in the first embodiment. In addition, in this embodiment, at least some of the effects described in the first embodiment can be obtained.

[0125] (Modification) In the above-described embodiment, the irradiation unit 91 irradiates ultraviolet rays onto the passage P between the suction port 11 and the coarse dust filter 60. However, in the present disclosure, the irradiation unit 91 may irradiate ultraviolet rays onto a space downstream of the suction port 11 and upstream of the fan 30 in the direction of the airflow generated by the fan 30. For example, an irradiation unit may be provided that irradiates ultraviolet rays onto the passage between the coarse dust filter 60 and the fan 30 in the direction of the airflow.

[0126] In the present disclosure, the term "ceiling-mounted type" includes not only a ceiling-embedded type as in the above-described embodiment, but also a ceiling-suspended type (a configuration in which the casing 10 is attached to the ceiling C with the casing 10 protruding downward from the ceiling surface C1), etc. Furthermore, the air conditioner of the present disclosure is not limited to a ceiling-mounted type, and may be a floor-standing type, wall-mounted type, or other type of air conditioner.

[0127] The number of air outlets is four in the above-described embodiment, but may be any number equal to or greater than two. The number of air outlets may be the same as the number of air inlets, or may be less than the number of air inlets, as long as there are more than one. The air inlet is configured with multiple through holes in the above-described embodiment, but may be configured with a single through hole.

[0128] The irradiation unit 91 may irradiate ultraviolet light other than UVC (for example, UVA with a wavelength of 320 to 400 nanometers, or UVB with a wavelength of 280 to 320 nanometers). However, among UVA, UVB, and UVC, UVC has the strongest sterilization effect.

[0129] In the above-described embodiment, the irradiation units are arranged on one or two of the four faces S1, S2, S3, and S4 that make up the passage P, but the irradiation units may also be arranged on one or two of the four sides that make up the suction port 11. In this case, it is preferable that the irradiation units are located at positions excluding the four corners of the four sides that make up the suction port 11, and further, at positions excluding the centers of each of the four sides that make up the suction port 11. This makes it possible to further reduce the area where the ultraviolet light intensity is weak.

[0130] In the above-described embodiment, the passage P is a quadrangular prism with a square horizontal cross section, but the passage P may also be a quadrangular pyramid with a cross-sectional area that increases or decreases toward the top. Also, in the present disclosure, the four corners may be chamfered so that the flat surfaces are connected with rounded corners, rather than being connected at right angles, or the four corners may be chamfered to form angular faces.

[0131] In the fourth embodiment, the two irradiation units 91A and 91B do not have to be arranged point-symmetrically. Furthermore, the two irradiation units 91A and 91B may be arranged on two adjacent surfaces instead of on two opposing surfaces. In the fourth embodiment, the two irradiation units 91A and 91B may be located at the center XA in the direction connecting both ends of the surface S1, the center XB in the direction connecting both ends of the surface S3, or at the corners C1 and C3.

[0132] The air conditioner may further include a heat exchanger, thereby providing heating and / or cooling functions.

[0133] In the above embodiment, the blowing direction is four directions, but it may be two directions, three directions, or the like.

[0134] The fan may be adjacent to the air inlet.

[0135] The sterilization unit 90 does not need to include the active species generation unit 92 as long as it has the irradiation unit 91 .

[0136] In the above-described embodiment, instead of the HEPA filter 51, a medium- to high-performance filter having a lower collection efficiency than the HEPA filter 51 (for example, having a predetermined collection efficiency for particles with a particle size of more than 0.3 μm) may be used as the second filter of the present disclosure.

[0137] In the above-described embodiment, the straightening member 40 may not have the lower portion 42 , and the coarse dust filter 60 may be attached to the lower surface of the upper portion 41 of the straightening member 40 .

[0138] In the present disclosure, "when the support member is removed from the casing" includes both a case where a portion of the support member is supported by the casing and a portion of the support member other than that portion is separated from the casing, as in the above-described embodiment (see Figures 6 and 7), and a case where the entire support member is separated from the casing.

[0139] In the above-described embodiment, the limit switch 200 is provided around the periphery of the opening 10x of the casing 10, and when the intake grille 20 is removed from the casing 10, the circuit of the limit switch 200 is opened and UVC irradiation by the UVC-LED 95 is stopped, but this is not limiting. For example, a proximity sensor may be provided, and when the control unit detects that the intake grille 20 has been removed from the casing 10 by a signal from the proximity sensor, UVC irradiation by the UVC-LED 95 may be stopped.

[0140] In the above-described embodiment, even if the protrusion 21 contacts the contact member 210 and UVC irradiation by the UVC-LED 95 is possible, if the ambient temperature of the irradiation unit 91 is equal to or higher than a predetermined temperature, UVC irradiation by the UVC-LED 95 may be stopped. If UVC irradiation is continued when the ambient temperature is high, deterioration of the irradiation unit 91 will progress, but this can be suppressed with the present configuration.

[0141] The protrusion may be disposed in the first region.

[0142] The protrusion may be provided on only one of the four sides of the support member. The attachment portion may be provided on only one of the four sides of the opening.

[0143] In the above-described embodiment, the irradiation unit can irradiate ultraviolet light when the protrusion of the support member comes into contact with the contact portion, but this is not limited to this. For example, the irradiation unit may be able to irradiate ultraviolet light when a portion of the support member other than the protrusion comes into contact with the contact portion. In this case, it is not necessary to provide a protrusion on the support member.

[0144] In the above-described embodiment, the protruding portion 20z corresponds to the "mounting portion" and the recessed portion 10z corresponds to the "mounted portion" of the present disclosure, but is not limited thereto. For example, a recessed portion corresponding to the "mounting portion" of the present disclosure may be provided on the support member, and a protruding portion corresponding to the "mounted portion" of the present disclosure may be provided on the casing.

[0145] The support member is not limited to being rotatably supported relative to the casing. For example, the support member may not be rotatably supported relative to the casing, but may be fixed to the casing with screws, bolts, or the like.

[0146] Although the embodiments have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the claims.

[0147] REFERENCE SIGNS LIST 1 Air conditioner 10 Casing 10x Opening 10x1 First side 10x2 Second side 10x3 Third side 10x4 Fourth side 10z Recessed portion (mounting portion) 11 Intake port 12 Outlet 20 Intake grille (support member) 20x5 Fifth side 20x6 Sixth side 20x7 Seventh side 20x8 Eighth side 20z Convex portion (mounting portion) 20r1 Central region (first region) 20r2 Edge region (second region) 21 Protrusion 30 Fan 40 Straightening member 41 Upper portion (first portion) 42 Lower portion (second portion) 51 HEPA filter (second filter) 60 Coarse dust filter (first filter) 70 Pre-filter (third filter) 90 Sterilization section 91 Irradiation section 92 Active species generating unit 95 UVC-LED 97 Shielding member (member) 100 Control unit 110 Notification unit 120 Sensor 200 Limit switch 210 Contact member (contact unit) C Ceiling P Passage R Space S1 to S4 Four sides

Claims

1. An air conditioner (1) comprising: a casing (10) having an intake port (11) and a plurality of exhaust ports (12); a fan (30) disposed within the casing (10) for generating an airflow within the casing (10) from the intake port (11) to the exhaust ports (12); and an irradiation unit (91) disposed within the casing (10) for irradiating ultraviolet rays, wherein the irradiation unit (91) irradiates ultraviolet rays to a space downstream of the intake port (11) and upstream of the fan (30) in the direction of the airflow.

2. The air conditioner (1) according to claim 1, which is a ceiling-mounted type.

3. The air conditioner (1) according to claim 2, wherein the direction (D) of ultraviolet light emitted from the irradiating section (91) is directed vertically upward from the horizontal.

4. The air conditioner (1) according to any one of claims 1 to 3, wherein the air intake (11) is rectangular, and a passage (P) for the airflow formed by four sides (S1 to S4) is provided from the air intake (11) to the fan (30), and the irradiation unit (91) is arranged on one of the four sides of the air intake (11) excluding the four corners, or on a face (S1) of the four sides (S1 to S4) of the passage (P) excluding the four corners, and irradiates ultraviolet light into the passage (P).

5. The air conditioner (1) according to claim 4, wherein the irradiation section (91) is arranged at a position excluding the center of each of the four sides of the air inlet (11), or at a position (Y) excluding the center (X) in a direction connecting both ends of each of the four faces (S1 to S4) of the passage (P).

6. The air conditioner (1) according to claim 4 or 5, wherein the irradiation section (91) includes: a first irradiation section (91A) arranged on a first side of the four sides of the suction port (11) or a first surface (S1) of the four surfaces (S1 to S4) of the passage (P); and a second irradiation section (91B) arranged on a second side opposite the first side of the four sides of the suction port (11) or a second surface (S3) opposite the first surface (S1) of the four surfaces (S1 to S4) of the passage (P).

7. An air conditioner (1) as described in any one of claims 1 to 6, further comprising a first filter (60) arranged downstream of the intake port (11) and upstream of the fan (30) in the direction of the airflow within the casing (10), and wherein the irradiation section (91) irradiates ultraviolet light into a space (R) upstream of the first filter (60) in the direction of the airflow.

8. An air conditioner (1) according to any one of claims 1 to 7, further comprising a member (97) that restricts ultraviolet light emitted from the irradiation section (91) from heading toward the air inlet (11).

9. The air conditioner (1) according to any one of claims 1 to 8, wherein the irradiation section (91) includes a UVC-LED (95).

10. An air conditioner (1) as described in any one of claims 1 to 6, comprising: a second filter (51) arranged downstream of the fan (30) in the direction of the airflow within the casing (10); and a sterilization section (90) arranged within the casing (10) for sterilizing the space downstream of the intake port (11) and upstream of the fan (30) in the direction of the airflow.

11. An air conditioner (1) as described in claim 10, further comprising a first filter (60) arranged downstream of the intake port (11) and upstream of the fan (30) in the direction of the air flow within the casing (10).

12. An air conditioner (1) as described in claim 11, wherein the minimum size of particles for which a predetermined collection efficiency can be achieved by the second filter (51) is smaller than the minimum size of particles for which the predetermined collection efficiency can be achieved by the first filter (60).

13. The air conditioner (1) according to claim 11 or 12, wherein the sterilization section (90) includes the irradiation section (91).

14. The air conditioner (1) according to claim 13, wherein the irradiation section (91) irradiates ultraviolet light toward the first filter (60).

15. An air conditioner (1) as described in any one of claims 11 to 14, further comprising a third filter (70) arranged downstream of the intake port (11) and upstream of the first filter (60) in the direction of the airflow within the casing (10), wherein the minimum size of particles for which a predetermined collection efficiency can be achieved by the third filter (70) is larger than the minimum size of particles for which the predetermined collection efficiency can be achieved by the first filter (60).

16. An air conditioner (1) as described in claim 15, wherein the sterilization section (90) sterilizes the space downstream of the third filter (70) and upstream of the first filter (60) in the direction of the airflow.

17. An air conditioner (1) as set forth in any one of claims 11 to 16, further comprising a rectifying member (40) that rectifies the air flow from the air inlet (11) to the fan (30), the rectifying member (40) having a first portion (41) and a second portion (42) that is closer to the air inlet (11) than the first portion (41) and has a larger diameter than the first portion (41), and the first filter (60) is attached to the second portion (42).

18. An air conditioner (1) according to any one of claims 10 to 17, wherein the sterilization section (90) includes an active species generation section (92).

19. An air conditioner (1) according to any one of claims 10 to 18, wherein the second filter (51) is a HEPA filter.

20. An air conditioner (1) as described in any one of claims 1 to 19, further comprising: a control unit (100) that controls the irradiation unit (91); and a sensor (120) that detects the ambient temperature of the irradiation unit (91), wherein the control unit (100) stops the irradiation of ultraviolet rays by the irradiation unit (91) when the ambient temperature is equal to or higher than a predetermined temperature.

21. A ceiling-mounted air conditioner (1) according to any one of claims 1 to 14, further comprising: a third filter (70); and a support member (20) that supports the third filter (70), the support member (20) being detachable from the casing (10), and the irradiation unit (91) stopping irradiation of ultraviolet light when the support member (20) is removed from the casing (10).

22. An air conditioner (1) as described in claim 21, wherein the casing (10) has a contact portion (210), and when the support member (20) comes into contact with the contact portion (210), ultraviolet light can be irradiated by the irradiation portion (91).

23. An air conditioner (1) as described in claim 22, wherein the support member (20) has a protrusion (21), and when the protrusion (21) comes into contact with the contact portion (210), ultraviolet light can be irradiated by the irradiation portion (91).

24. An air conditioner (1) as described in claim 23, wherein the support member (20) has an attachment portion (20z) at one end and is rotatable relative to the casing (10) around the attachment portion (20z), and the protrusion (21) is arranged at the other end of the support member (20).

25. The support member (20) is rectangular, the casing (10) has a rectangular opening (10x) covered by the support member (20), the opening (10x) has a first side (10x1) on which the contact portion (210) is arranged, a second side (10x2), a third side (10x3), and a fourth side (10x4), the second side (10x2), the third side (10x3), and the fourth side (10x4) are provided with attached portions (10z) corresponding to the attaching portion (20z), the support member (20) has a fifth side (20x5) constituting the one end, and a sixth side (20x6), a seventh side (20x7), and an eighth side (20x8) constituting the other end, The air conditioner (1) according to claim 24, wherein the protrusions (21) are arranged on the sixth side (20x6), the seventh side (20x7), and the eighth side (20x8).

26. An air conditioner (1) as described in any one of claims 23 to 25, wherein the support member (20) has a first region (20r1) that supports the third filter (70) and a second region (20r2) outside the first region, and the protrusion (21) is arranged in the second region (20r2).

27. An air conditioner (1) according to any one of claims 23 to 26, wherein the contact portion (210) is larger in size than the protrusion (21).

28. An air conditioner (1) according to any one of claims 20 to 27, further comprising an alarm unit (110) that notifies the user that ultraviolet radiation by the radiation unit (91) has stopped.