Ultraviolet irradiation device and air conditioner

Abstract

An ultraviolet irradiation device (60) includes an irradiation section (61) disposed on one end side in a first direction of a processing space (R), and a first reflection section (70) disposed on the other end side in the first direction of the processing space (R). The irradiation section (61) includes a surface light source (62) having an emission surface (65), and a lens (67) and a reflector (68) as optical members (OP) that condense ultraviolet rays emitted from the surface light source (62) toward the first reflection section (70). The lens (67) and the reflector (68) generate a paraxial image surface (90) of the emission surface (65) on an irradiated surface (71a) of the first reflection section (70) that is irradiated with the ultraviolet rays.

Description

Technical Field

[0001] This disclosure relates to ultraviolet irradiation devices and air conditioners. Background Technology

[0002] Patent Document 1 discloses an ultraviolet (UV) irradiation device for an air conditioner. This UV irradiation device is disposed within the housing of the indoor unit and irradiates UV light towards the ventilation path within the housing. The UV irradiation device includes a UV light-emitting diode (LED) for irradiating UV light and a reflective component for reflecting the UV light emitted from the LED.

[0003] The ultraviolet (UV) light-emitting diode (LED) and the reflector are positioned such that air flowing in the ventilation path passes between them. UV light irradiated by the LED is converted into parallel light and then shines on the reflector. The UV light reflected by the reflector is then directed back towards the LED along the optical axis of the parallel light. Thus, the UV light refluxing between the LED and the reflector irradiates the air flowing in the ventilation path, thereby inactivating viruses and bacteria in the air.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2022-126495 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In the ultraviolet irradiation device disclosed in Patent Document 1, a surface light source with a light-emitting surface is used as an ultraviolet light-emitting diode. Even with the combination of lenses and reflectors, it is difficult to make the ultraviolet light emitted from the surface light source completely parallel. If the ultraviolet light emitted from the ultraviolet light-emitting diode spreads in the direction of travel, it will spread further when reflected by the first reflector. Therefore, it is not possible to efficiently irradiate air flowing in processing spaces such as ventilation ducts with ultraviolet light.

[0009] The purpose of this disclosure is to efficiently irradiate air flowing in a processing space with ultraviolet light.

[0010] Methods for solving problems

[0011] The first aspect of this disclosure pertains to an ultraviolet irradiation apparatus 60 that irradiates ultraviolet light into a processing space R through which airflow is supplied. The ultraviolet irradiation apparatus 60 of the first aspect includes: an irradiation unit 61 disposed at one end of the processing space R in a first direction, irradiating ultraviolet light toward the other end in the first direction; and a first reflector 70 disposed at the other end of the processing space R in the first direction, reflecting the ultraviolet light irradiated from the irradiation unit 61 toward the end in the first direction. The irradiation unit 61 includes: a surface light source 62 having a light-emitting surface 65 that emits ultraviolet light; and an optical component OP that focuses the ultraviolet light emitted from the surface light source 62 toward the first reflector 70. The optical component OP is configured to generate a paraxial image plane 90 of the light-emitting surface 65 on the irradiated surface 71a of the irradiated ultraviolet light in the first reflector 70.

[0012] In this first embodiment, the irradiation unit 61 is disposed at one end of the processing space R, and the first reflector 70 is disposed at the other end of the processing space R. The irradiation unit 61 concentrates ultraviolet light emitted from the surface light source 62 toward the first reflector 70 via an optical component OP. The optical component OP generates a paraxial image plane 90 of the emitting surface 65 on the irradiated surface 71a of the irradiated ultraviolet light on the first reflector 70. As a result, the propagation of ultraviolet light reflected from the irradiated surface 71a of the first reflector 70 in the direction of travel can be suppressed. Thus, ultraviolet light can be efficiently irradiated onto the air flowing in the processing space R.

[0013] In the second aspect of the ultraviolet irradiation apparatus 60 disclosed herein, the irradiation unit 61 has a lens as the optical component OP, which refracts ultraviolet light emitted from the surface light source 62. The ultraviolet light emitted from the surface light source 62 has a wavelength of 200 nm or more and 300 nm or less.

[0014] In this second method, the ultraviolet light emitted from the surface light source 62 has a relatively short wavelength of 200 nm to 300 nm. The shorter the wavelength of the ultraviolet light, the easier it is to refract in the lens 67. Therefore, by using the lens 67, the ultraviolet light emitted from the surface light source 62 can be easily adjusted to form a paraxial image plane 90 of the luminescent surface 65 generated on the irradiated surface 71a of the first reflector 70. Furthermore, the aforementioned relatively short wavelength ultraviolet light is suitable for inactivating viruses and bacteria in the air.

[0015] In the third aspect of this disclosure, in the ultraviolet irradiation device 60 of the first or second aspect, the width of the paraxial image plane 90 in a specified direction is more than 20 mm and less than 70 mm.

[0016] In this third approach, the width of the paraxial image plane 90 in the specified direction is 20 nm or more and 70 mm or less. When a paraxial image plane 90 of this size is generated on the irradiated surface 71a, the ultraviolet irradiation device 60 can be made into a relatively compact structure. Therefore, the ultraviolet irradiation device 60 can be installed even in the limited space inside existing equipment such as an air conditioner 10.

[0017] In the fourth aspect of this disclosure, in a third-party ultraviolet irradiation device 60, the irradiation unit 61 has a lens 67 as the optical component OP, which refracts ultraviolet light emitted from the surface light source 62. The lens 67 is disposed on the front side of the emitting surface 65. When the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, i.e., the irradiation distance, is set as Li [mm], and the maximum width of the emitting surface 65 in a predetermined direction is set as Wl [mm], the distance La [mm] between the principal point P1 of the lens 67 and the emitting surface 65 satisfies the following relationship: Li×Wl / (70+Wl)≤La≤Li×Wl / (20+Wl).

[0018] In this fourth method, the distance La between the principal point P1 of the lens 67 and the emitting surface 65 is more than Li×Wl / (70+Wl) and less than Li×Wl / (20+Wl). As a result, a paraxial image plane 90 with a width of more than 20 nm and less than 70 mm in a predetermined direction can be generated on the irradiated surface 71a of the first reflecting part 70.

[0019] The fifth aspect of the ultraviolet irradiation device 60 disclosed herein, in the third or fourth aspect of the ultraviolet irradiation device 60, includes an irradiation unit 61 having a reflector 68 as the optical component OP, the reflector 68 reflecting ultraviolet light emitted from the surface light source 62. The reflector 68 is configured to surround the space on the front side of the emitting surface 65. The reflecting surface 68a of the reflector 68, which reflects ultraviolet light, is an approximately parabolic surface. When the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, i.e., the irradiation distance, is set as Li [mm], and the maximum width of the emitting surface 65 in a predetermined direction is set as Wl [mm], the distance Lb [mm] between the vertex P2 of the approximately parabolic surface 68a and the emitting surface 65 satisfies the following relationship: Li×Wl / (70-Wl)≤Lb≤Li×Wl / (20-Wl).

[0020] In this fifth method, the distance Lb between the vertex P2 of the parabolic surface approximating the reflecting surface 68a and the emitting surface 65 is more than Li×Wl / (70-Wl) and less than Li×Wl / (20-Wl). Therefore, a paraxial image plane 90 with a width of more than 20 nm and less than 70 mm in a predetermined direction can be generated on the irradiated surface 71a of the first reflecting portion 70.

[0021] In the sixth embodiment of the ultraviolet irradiation device 60 disclosed herein, in any of the third to fifth embodiments of the ultraviolet irradiation device 60, the irradiation unit 61 has a lens 67 and a reflector 68 as optical components OP. The lens 67 refracts ultraviolet rays emitted from the surface light source 62, and the reflector 68 reflects the ultraviolet rays emitted from the surface light source 62. The lens 67 is disposed on the front side of the emitting surface 65. The reflector 68 is configured to surround the space on the front side of the emitting surface 65 and the lens 67. When the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, i.e., the irradiation distance, is set to Li [mm], and the maximum width of the emitting surface 65 in a predetermined direction is set to Wl [mm], the angle θ [°] at the position of the emitting surface 65 located on the optical axis A0 of the lens 67, which becomes the distribution boundary of the light to the lens 67 and the reflector 68, satisfies the following relationship: θ≤arctan(35×(70-Wl) / Li×Wl), where θ≤89.

[0022] In this sixth approach, at the position of the emitting surface 65 located on the optical axis A0 of the lens 67, the angle θ that forms the boundary between the light distribution of the lens 67 and the reflector 68 is at least 89° and at least arctan(35 × (70 - Wl) / Li × Wl). Therefore, the diameter of the lens 67 converges to the maximum dimension of the paraxial image plane 90 in the specified direction, which is 70 mm or less. Thus, it is possible to use a lens 67 with a relatively small diameter to generate a paraxial image plane 90 with a width of 20 nm or more and 70 mm or less in the specified direction on the irradiated surface 71a of the first reflecting portion 70. This facilitates the realization of the ultraviolet irradiation device 60 with a compact structure.

[0023] In the ultraviolet irradiation device 60 of any of the first to sixth embodiments of this disclosure, the irradiated surface 71a is composed of a concave surface with a predetermined curvature. When the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, i.e., the irradiation distance, is set to Li [mm], the radius of curvature R1 of the irradiated surface 71a satisfies the following relationship: 0.5×Li≤R1≤2×Li.

[0024] In this seventh embodiment, the radius of curvature R1 of the irradiated surface 71a of the first reflector 70 is greater than 0.5 times the irradiation distance Li and less than 2 times the irradiation distance Li. The irradiated surface 71a with such a radius of curvature R1 can reflect ultraviolet rays irradiated from the irradiation unit 61 towards the vicinity of the irradiation unit 61. Therefore, the ultraviolet irradiation device 60 has a compact structure and can be used in relatively narrow processing spaces R.

[0025] The eighth aspect of the ultraviolet irradiation device 60 of this disclosure, in any one of the first to seventh aspects of the ultraviolet irradiation device 60, includes a second reflective part 80, which is disposed at one end of the processing space R in the first direction and reflects the ultraviolet rays reflected by the first reflective part 70 toward the other end of the first direction.

[0026] In this eighth embodiment, the second reflector is positioned at one end of the processing space R in the first direction, i.e., the same side as the irradiation unit 61. Ultraviolet light reflected by the first reflector 70 is reflected again by the second reflector 80 towards the other end in the first direction. This allows the ultraviolet light emitted from the irradiation unit 61 to be repeatedly reflected between the first reflector 70 and the second reflector 80, resulting in a longer residence time in the processing space R. This is beneficial for efficiently irradiating the air flowing in the processing space R with ultraviolet light.

[0027] In the ninth embodiment of the ultraviolet irradiation device 60 disclosed herein, in any one of the first to eighth embodiments of the ultraviolet irradiation device 60, the irradiation unit 61 has a lens 67 as the optical component OP, the lens 67 refracting ultraviolet rays emitted from the surface light source 62. The lens 67 is a biconvex lens having a first surface 67a located on the surface light source 62 side and a second surface 67b located on the first reflective part 70 side, wherein the first surface 67a and the second surface 67b are both convex. The radius of curvature of the first surface 67a is greater than the radius of curvature of the second surface 67b.

[0028] In this ninth embodiment, the radius of curvature of the first surface 67a of the lens 67 located on the side of the surface light source 62 is greater than the radius of curvature of the second surface 67b located on the side of the first reflector 70. If the radius of curvature of the first surface 67a is smaller than that of the second surface 67b, the distance between the principal point P1 of the lens 67 and the surface light source 62 becomes shorter, and the magnification of the paraxial image plane 90 becomes larger. Therefore, it is not suitable to generate a paraxial image plane 90 that converges within its dimensions on the irradiated surface 71a of the first reflector 70. Conversely, if the radius of curvature of the first surface 67a is greater than that of the second surface 67b, the distance between the principal point P1 of the lens 67 and the surface light source 62 becomes longer, and the magnification of the paraxial image plane 90 becomes smaller. Therefore, it is possible to prevent ultraviolet light irradiated from the irradiation section 61 from leaking from the first reflector 70, while simultaneously constructing the ultraviolet irradiation device 60 compactly.

[0029] In the tenth aspect of the present disclosure, in the ultraviolet irradiation device 60 of the ninth aspect, the first surface 67a and the second surface 67b are both even-order aspherical surfaces.

[0030] In this tenth embodiment, the first surface 67a and the second surface 67b of the lens 67 are both even-order aspherical surfaces. This reduces aberrations contained in the paraxial image plane 90. This is beneficial for suppressing the propagation of ultraviolet light reflected from the irradiated surface 71a of the first reflector 70 in the direction of travel.

[0031] The eleventh aspect of this disclosure pertains to an air conditioner 10. The air conditioner 10 of the eleventh aspect includes: a housing 31 having an air intake 32, an air outlet 33, and an airflow path 34 extending from the air intake 32 to the air outlet 33; and an ultraviolet irradiation device 60 that irradiates a portion of the airflow path 34 as a processing space R with ultraviolet light. The ultraviolet irradiation device 60 is an ultraviolet irradiation device 60 of any of the first to tenth aspects.

[0032] In this eleventh method, an ultraviolet irradiation device 60 of any of the first to tenth methods is used. This ultraviolet irradiation device 60 is capable of efficiently irradiating the air flowing in the processing space R with ultraviolet light. Therefore, in the air conditioner 10, ultraviolet-based inactivation of viruses and bacteria in the air can be effectively performed. Attached Figure Description

[0033] Figure 1 This is a piping system diagram of the air conditioner according to the implementation method.

[0034] Figure 2 This is the front view showing the exterior of the interior unit.

[0035] Figure 3 It is along the indoor unit Figure 2 A cross-sectional view along line AA.

[0036] Figure 4 This is a diagram showing the indoor heat exchanger as viewed from the outflow side.

[0037] Figure 5 This is a schematic diagram of the irradiation section.

[0038] Figure 6 This is a schematic diagram of the structure of a surface light source.

[0039] Figure 7 It is a graph that shows the change in refractive index in the same material corresponding to the wavelength range of light.

[0040] Figure 8This is a perspective view illustrating the structure of an optical system for generating a paraxial image plane of the luminescent surface of the irradiated surface of the first reflective portion.

[0041] Figure 9 This is a diagram illustrating the distribution of ultraviolet radiation intensity in the paraxial image plane generated on the irradiated surface of the first reflector.

[0042] Figure 10 This is a schematic diagram showing the main parts of an ultraviolet irradiation device.

[0043] Figure 11 It uses arrows to indicate the direction of ultraviolet light travel in the ultraviolet irradiation device, equivalent to... Figure 4 The image.

[0044] Figure 12 This is a modified example of an air conditioner. Figure 3 The image. Detailed Implementation

[0045] The illustrated embodiments will now be described in detail based on the accompanying drawings. In these embodiments, the application of the ultraviolet irradiation device of this disclosure to an air conditioner will be used as an example. Furthermore, the accompanying drawings are provided to conceptually illustrate the technology of this disclosure. Therefore, in the accompanying drawings, dimensions, ratios, or quantities are sometimes exaggerated or simplified to facilitate understanding of the technology of this disclosure.

[0046] (1) Overview of air conditioners

[0047] An ultraviolet irradiation device 60 is applied to an air conditioner 10. The air conditioner 10 regulates the air in the indoor space S1, which is the target space. The air conditioner 10 regulates the temperature of the indoor air.

[0048] like Figure 1 As shown, the air conditioner 10 is a paired air conditioner, comprising one outdoor unit 20 and one indoor unit 30. The outdoor unit 20 is located outdoors. The indoor unit 30 is located indoors. The outdoor unit 20 and the indoor unit 30 are interconnected via a first connecting pipe 12 and a second connecting pipe 13.

[0049] The outdoor unit 20, indoor unit 30, first connecting pipe 12, and second connecting pipe 13 constitute a refrigerant circuit 11. The refrigerant circuit 11 is filled with refrigerant. The refrigerant circuit 11 mainly includes a compressor 21, an outdoor heat exchanger 22, an expansion valve 23, a four-way reversing valve 24, and an indoor heat exchanger 50. The compressor 21, outdoor heat exchanger 22, expansion valve 23, four-way reversing valve 24, and indoor heat exchanger 50 are connected in series via piping.

[0050] The compressor 21, outdoor heat exchanger 22, expansion valve 23, and four-way reversing valve 24 are included in the outdoor unit 20. The outdoor unit 20 also includes an outdoor fan 25.

[0051] Compressor 21 compresses the incoming refrigerant and discharges the compressed refrigerant. Outdoor fan 25, driven by a fan motor, rotates to deliver outdoor air through outdoor heat exchanger 22. Outdoor heat exchanger 22 facilitates heat exchange between the refrigerant flowing within it and the outdoor air delivered by outdoor fan 25. Expansion valve 23 reduces the pressure on the refrigerant.

[0052] The four-way reversing valve 24 switches the refrigerant flow direction during cooling and heating operations. During cooling operation, the four-way reversing valve 24 is in its first state (…). Figure 1 (As shown by the dashed line), the refrigerant flows in the direction of the arrow pointing towards the dashed line. During heating operation, the four-way reversing valve 24 enters the second state (…). Figure 1 (The solid line indicates the state), and the refrigerant flows toward the arrow pointing towards the solid line.

[0053] The indoor heat exchanger 50 is included in the indoor unit 30. That is, the indoor unit 30 has the indoor heat exchanger 50. The indoor unit 30 also has an indoor fan 42.

[0054] The indoor fan 42 is driven by a fan motor to rotate, conveying indoor air through the indoor heat exchanger 50. The indoor heat exchanger 50 facilitates heat exchange between the refrigerant flowing within it and the indoor air conveyed by the indoor fan 42. The air after passing through the indoor heat exchanger 50 is then delivered to the indoor space S1.

[0055] (2) Structure of the indoor unit

[0056] Reference Figures 2-4 The structure of the interior unit 30 will be described. Additionally, in the following description, statements related to "front," "rear," "right," "left," "upper," and "lower" will be... Figure 2 and Figure 3 The direction indicated by the middle arrow is the reference.

[0057] The indoor unit 30 in this embodiment is a wall-mounted indoor air conditioner, installed on the wall of the indoor space S1. The indoor unit 30 includes a housing 31, an air filter 41, an indoor heat exchanger 50, an indoor fan 42, a drain tray 43, and a baffle 44. The air filter 41, the indoor heat exchanger 50, the indoor fan 42, the drain tray 43, and the baffle 44 are housed in the housing 31.

[0058] (2-1) Shell

[0059] The housing 31 constitutes a flow path forming component for forming the air flow path 34. The housing 31 is formed as a hollow box shape that is horizontally elongated in the left-right direction. The length direction of the housing 31 corresponds to the left-right direction.

[0060] An intake port 32 and an outlet port 33 are formed in the housing 31. The intake port 32 is an opening for drawing air from the interior space SI into the interior of the housing 31. The outlet port 33 is an opening for blowing air from the interior of the housing 31 into the interior space SI. Inside the housing 31, an airflow path 34 is formed from the intake port 32 to the outlet port 33.

[0061] (2-2) Air filter

[0062] An air filter 41 is disposed upstream of the indoor heat exchanger 50 in the airflow path 34. The air filter 41 is disposed along the inside of the intake 32. The air filter 41 is installed in the housing 31 such that substantially all air supplied to the indoor heat exchanger 50 passes through it. The air filter 41 is a mesh component. The air filter 41 captures dust particles in the air drawn in from the intake 32.

[0063] (2-3) Indoor heat exchanger

[0064] The indoor heat exchanger 50 is positioned upstream of the indoor fan 42 in the airflow path 34. For example... Figure 3 As shown, the indoor heat exchanger 50 is arranged within the housing 31 such that it covers the front of the indoor fan 42 from above and also covers the rear side above the indoor fan 42. In this example, the indoor heat exchanger 50 is a finned tube type heat exchanger.

[0065] The indoor heat exchanger 50 has multiple fins 51 and heat transfer tubes 52. The multiple fins 51 are arranged in a parallel configuration in a first direction. In this example, the first direction corresponds to the left-right direction. The fins 51 are composed of generally rectangular plates extending in a direction orthogonal to the first direction. Ventilation paths are formed between adjacent fins 51, allowing air to pass through. The fins 51 are made of, for example, aluminum.

[0066] The heat transfer tube 52 has a straight section 52a and a U-shaped section 52b. The straight section 52a has multiple fins 51 extending through it in the thickness direction. The direction in which the straight section 52a extends corresponds to a first direction. The U-shaped section 52b has a U-shaped shape and integrally connects the ends of the straight section 52a to each other. The U-shaped section 52b is located on the side of the heat exchange section. Refrigerant flows inside the heat transfer tube 52.

[0067] (2-4) Indoor fans, drain trays and baffles

[0068] The indoor fan 42 is an example of a fan. The indoor fan 42 is a cross-flow fan. The indoor fan 42 is positioned approximately in the central portion of the airflow path 34. The indoor fan 42 rotates under the drive of a fan motor. The direction of the rotation axis of the indoor fan 42 corresponds to a first direction. In other words, the indoor fan 42 has a shape with the first direction as its length.

[0069] A drain pan 43 is disposed on the underside of the indoor heat exchanger 50. The drain pan 43 is a tray that receives water generated within the housing 31. Condensation generated on the surface of the indoor heat exchanger 50 is received by the drain pan 43. A drain pump (not shown) is disposed inside the drain pan 43. The drain pump draws up the water accumulated in the drain pan 43 and discharges it to the outside via a drain hose.

[0070] The baffle 44 constitutes an airflow regulating section for adjusting the direction of air blown from the outlet 33. The baffle 44 is formed as an elongated plate extending along the length of the outlet 33. The baffle 44 is disposed at the outlet 33. The baffle 44 is rotated by a motor, adjusting the airflow direction from the outlet 33 in the vertical direction. The indoor unit 30 may also include louvers as an airflow regulating section for adjusting the airflow direction from the outlet 33 in the horizontal direction.

[0071] (3) Ultraviolet irradiation device

[0072] (3-1) Overall Structure

[0073] like Figure 3 as well as Figure 4 As shown, the air conditioner 10 is equipped with an ultraviolet irradiation device 60.

[0074] An ultraviolet (UV) irradiation device 60 is disposed in the airflow path 34 of the indoor unit 30. In this embodiment, the UV irradiation device 60 is located downstream of the indoor heat exchanger 50. The UV irradiation device 60 forms a processing space R on its downstream side (outflow surface) O1 along the airflow direction of the indoor heat exchanger 50. The length direction of the fins 51 corresponding to the surface of the indoor heat exchanger 50 along which the processing space R is located corresponds to a second direction. The UV irradiation device 60 uses a portion of the airflow path 34 as the processing space R, and irradiates the processing space R with UV light to inactivate viruses and bacteria in the airflow in the processing space R.

[0075] like Figure 4As shown, the ultraviolet irradiation device 60 includes an irradiation section 61, a first reflector section 70, and a second reflector section 80. The irradiation section 61 and the second reflector section 80 are disposed at one end of the processing space R in a first direction. The first reflector section 70 is disposed at the other end of the processing space R in the first direction. The irradiation section 61 irradiates ultraviolet light. The first reflector section 70 reflects the ultraviolet light irradiated by the irradiation section 61. The second reflector section 80 reflects the ultraviolet light reflected by the first reflector section 70.

[0076] (3-2) Irradiation part

[0077] The irradiation unit 61 is supported on a first side plate 31a, which is one side plate in the left-right direction of the housing 31. Strictly speaking, in this embodiment, the irradiation unit 61 is indirectly supported on the first inner surface 35 of the first side plate 31a via a first reflective part 70. The first inner surface 35 is the surface of the first side plate 31a formed on the side of the airflow path 34. The irradiation unit 61 may also be directly supported on the first inner surface 35 of the first side plate 31a. The irradiation unit 61 may also be indirectly supported on the first side plate 31a via other components within the housing 31.

[0078] The irradiation section 61 is positioned on the first inner surface 35 in a V-shape near the front of the indoor heat exchanger 50. For example... Figure 5 As shown, the irradiation unit 61 includes a surface light source 62 and an optical component OP. The optical component OP is an optical element that focuses ultraviolet rays emitted from the surface light source 62 toward the first reflector 70. In this embodiment, the irradiation unit 61 includes a lens 67 and a reflector 68 as the optical component OP.

[0079] The surface light source 62 is a light-emitting device having a light-emitting surface 65 that emits ultraviolet light. The surface light source 62 is mounted on a circuit board 66. A heat dissipation component (not shown) is provided on the circuit board 66 to dissipate the heat generated by the surface light source 62. Figure 6 As shown, the surface light source 62 includes a packaging substrate 63 and a semiconductor chip 64. Wiring and electrodes are provided on the packaging substrate 63. The semiconductor chip 64 is mounted on the packaging substrate 63. The semiconductor chip 64 includes a light-emitting diode (LED).

[0080] The light-emitting surface 65 is the portion of the semiconductor chip 64 that emits light through an ultraviolet LED. The light-emitting surface 65 can also be formed by converging the light-emitting portions of multiple ultraviolet LEDs. In this embodiment, the light-emitting surface 65 is rectangular. The light-emitting surface 65 has a pair of first sides 65a and a pair of second sides 65b. The pair of first sides 65a and the pair of second sides 65b are opposite sides. The first sides 65a and the second sides 65b extend in mutually orthogonal directions.

[0081] In this example, the light-emitting surface 65 is formed into a square shape with the lengths of the first side 65a and the second side 65b being equal. The first side 65a and the second side 65b are both approximately 1 mm. The surface light source 62 is configured such that the first side 65a of the light-emitting surface 65 extends along a second direction, and the second side 65b extends along a third direction orthogonal to both the first and second directions.

[0082] The ultraviolet light emitted by the surface light source 62 has a wavelength of 200 nm or more and 300 nm or less. For example... Figure 7 As shown, the shorter the wavelength of ultraviolet light, the easier it is to refract in a lens. Furthermore, ultraviolet light with wavelengths between 200 nm and 300 nm is considered deep ultraviolet (UV-C) or near-deep ultraviolet (UV-C) and acts to inactivate viruses and bacteria in the air.

[0083] For example, the ultraviolet light irradiated by the surface light source 62 is deep ultraviolet light (UV-C) with a peak wavelength of 280 nm or less. This improves the air sterilization effect. From the viewpoint of improving the air sterilization effect, the peak wavelength of the ultraviolet light irradiated by the surface light source 62 is preferably 255 nm or more and 275 nm or less. The peak wavelength of the ultraviolet light irradiated by the surface light source 62 can be 230 nm or less. This improves safety for human exposure should ultraviolet light leak to the outside of the housing 31.

[0084] Lens 67 is disposed on the front side of the light-emitting surface 65 of the surface light source 62. Lens 67 is positioned such that the optical axis A0 is aligned with the direction of ultraviolet radiation emitted from the surface light source 62. Lens 67 is a transparent body that refracts ultraviolet radiation emitted from the surface light source 62, focusing the refracted ultraviolet radiation toward the first reflector 70. In this embodiment, lens 67 is a biconvex lens. Lens 67 has a first surface 67a and a second surface 67b. The first surface 67a and the second surface 67b are convex surfaces facing opposite sides in the thickness direction of lens 67.

[0085] The first surface 67a is located on the side of the surface light source 62. The second surface 67b is located on the side of the first reflector 70. The first surface 67a and the second surface 67b are both even-order aspherical surfaces. Thus, if an even-order aspherical surface is applied to the lens 67, spherical aberration can be corrected. The radius of curvature of the first surface 67a is greater than that of the second surface 67b. If the radius of curvature of the first surface 67a is smaller than that of the second surface 67b, the distance between the principal point P1 of the lens 67 and the surface light source 62 becomes shorter, and the magnification of the paraxial image plane 90 becomes larger. Therefore, it is not suitable to generate the paraxial image plane 90, which will be described later, with dimensions that converge to the range of the first reflector 71, which is set within a limited space inside the interior unit 30.

[0086] Reflector 68 is configured to surround the space on the front side of the surface light source 62 (light-emitting surface 65). Reflector 68 is a reflective component that reflects ultraviolet light emitted from the surface light source 62 and focuses the reflected ultraviolet light towards the first reflective portion 70. Reflector 68 has a reflective surface 68a that reflects ultraviolet light. The reflective surface 68a is a curved surface equivalent to or approximately a paraboloid of revolution. Figure 5 In the above, the shape of the rotating radiating surface is used to represent the entire reflector 68. However, as long as the reflecting surface 68a of the reflector 68 is formed into a shape equivalent to part of a rotating parabola, the reflector 68 can adopt the shape required to avoid interference in combination with the surface light source 62 and the lens 67.

[0087] like Figure 8 As shown, through lens 67 and reflector 68, the irradiation section 61 irradiates ultraviolet light towards the other end of the processing space R in a first direction. Figure 8 In the image, a dashed arrow indicates the approximate direction of ultraviolet radiation. Additionally, this is in... Figure 5 and Figure 11 The same applies to China.

[0088] Lens 67 and reflector 68 are configured such that the paraxial image plane 90 of the emitting surface 65 in the surface light source 62 is generated on the irradiated surface 71a of the first reflecting portion 70 where ultraviolet light is irradiated. Lens 67 and reflector 68 image the emitting surface 65 on or near the irradiated surface 71a of the first reflecting portion 70. The edges of the image plane generated on the irradiated surface 71a are slightly blurred due to aberrations. The paraxial image plane 90 is an image plane that includes such blurring (aberrations).

[0089] In this embodiment, the paraxial image plane 90 is rectangular, similar in shape to the emitting surface 65 of the surface light source 62. The paraxial image plane 90 has a pair of third sides 90a and a pair of fourth sides 90b. The pair of third sides 90a and the pair of fourth sides 90b are opposite sides. The third sides 90a and the fourth sides 90b extend in mutually orthogonal directions. The third side 90a is the side extending along a second direction. The fourth side 90b is the side extending along a third third direction. In this example, the paraxial image plane 90 is formed as a square with the lengths of the third sides 90a and 90b being equal.

[0090] like Figure 9As shown, the paraxial image plane 90 includes a first image plane region 91 formed by the focusing of light through lens 67 and reflector 68, and a second image plane region 92 formed by the focusing of light through lens 67. The first image plane region 91 constitutes the central portion of the paraxial image plane 90. The second image plane region 92 constitutes the portion of the paraxial image plane 90 other than the first image plane region 91. The ultraviolet illuminance distribution in the paraxial image plane 90 is relatively high in the first image plane region 91 and relatively low in the second image plane region 92. The ultraviolet illuminance distribution in the first image plane region 91 is also relatively lower at the edges than in other portions.

[0091] like Figure 10 As shown, the distance from the emitting surface 65 of the surface light source 62 to the principal point P1 of the lens 67 is defined as La [mm], and the distance from the principal point P1 of the lens 67 to the illuminated surface 71a of the first reflecting part 70 is defined as Lb [mm]. Strictly speaking, the latter distance Lb is the distance from the principal point P1 of the lens 67 to the position of the first reflecting surface 71 located on the optical axis A0 of the lens 67. In this case, the magnification β of the paraxial image plane 90 is expressed by the following Equation 1.

[0092] β = Lb / La… (Equation 1)

[0093] The irradiation distance of the irradiation unit 61 to the ultraviolet light of the first reflector 70 is set as Li [mm]. The irradiation distance Li is the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, or more precisely, the distance from the emitting surface 65 to the position of the irradiated surface 71a on the optical axis A0 of the lens 67. In this case, Lb = Li - La holds. Therefore, the distance La from the emitting surface 65 to the principal point P1 of the lens 67 is expressed by the following Equation 2.

[0094] La = Li / (β+1)...(Equation 2)

[0095] The length of the second side 65b of the emitting surface 65 is set to Wl [mm]. The length of the second side 65b is equivalent to the maximum width of the emitting surface 65 in a specified direction. The specified direction here can be understood as the direction with the narrowest width designed among the directions orthogonal to the first direction when the processing space R is formed in the airflow path 34. In addition, the length of the fourth side 90b of the paraxial image plane 90 is set to Wi. In this case, the magnification β of the paraxial image plane 90 is also expressed by the following Equation 3. By combining Equation 3 with Equation 2 above, the distance La from the emitting surface 65 to the principal point P1 of the lens 67 is expressed by the following Equation 4.

[0096] β = Wi / Wl… (Equation 3)

[0097] La=Li×Wl / (Wi+Wl)…(Formula 4)

[0098] In this embodiment, the lengths of the third side 90a and the fourth side 90b of the paraxial image plane 90 are 20 mm or more and 70 mm or less, respectively. The length of the fourth side 90b of the paraxial image plane 90 is equivalent to the width of the paraxial image plane 90 in a specified direction. Therefore, the distance La between the principal point P1 of the lens 67 and the emitting surface 65, based on the length of the fourth side 90b of the paraxial image plane 90, satisfies the relationship expressed by Equation 5 below. The positional relationship between the surface light source 62 and the lens 67 is designed to satisfy the relationship expressed by Equation 5.

[0099] Li×Wl / (70+Wl)≤La≤Li×Wl / (20+Wl)…(Formula 5)

[0100] Furthermore, the distance from the vertex P2 of the reflecting surface 68a in the reflector 68 to the emitting surface 65 of the surface light source 62 is defined as Lc [mm], and the distance from the vertex P2 of the reflecting surface 68a to the illuminated surface 71a of the first reflecting part 70 is defined as Ld [mm]. Strictly speaking, the latter distance Ld is the distance from the vertex P2 of the reflector 68 to the position on the optical axis A0 of the lens 67 in the first reflecting surface 71. In this case, the relationship between the distance Lc from the vertex P2 of the reflector 68 to the emitting surface 65 of the surface light source 62 and the magnification β of the paraxial image plane 90 is expressed by the following Equation 6. Equation 6 is obtained assuming that the light emitted from the surface light source 62 exits from the emitting surface 65 at a 360° angle.

[0101] Lc = Ld / β……(Equation 6)

[0102] Furthermore, between the aforementioned two distances Lc and Ld and the illumination distance Li, Ld = Lc + Li holds true. Therefore, the distance Lc from the vertex P2 of the reflecting surface 68a to the emitting surface 65 of the surface light source 62 is also expressed by the following equation 7. By combining this equation 7 with the above equation 3, the distance Lc from the vertex P2 of the reflecting surface 68a to the emitting surface 65 of the surface light source 62 is expressed by the following equation 8.

[0103] Lc = Li / (β-1)…(Equation 7)

[0104] Lc=Li×Wl / (Wi-Wl)…(Formula 8)

[0105] As described above, the lengths of the third side 90a and the fourth side 90b of the paraxial image plane 90 are 20 mm or more and 70 mm or less, respectively. Therefore, the distance Lc between the vertex P2 of the reflecting surface 68a and the emitting surface 65, based on the length of the fourth side 90b of the paraxial image plane 90, satisfies the relationship expressed by Equation 9 below. The positional relationship between the surface light source 62 and the reflector 68 is designed to satisfy the relationship expressed by Equation 9.

[0106] Li×Wl / (70-Wl)≤Lc≤Li×Wl / (20-Wl)…(Formula 9)

[0107] The surface light source 62 has a defined beam distribution angle. The beam distribution angle refers to the spread angle of the light (ultraviolet light) emitted from the surface light source 62. Specifically, the beam distribution angle is the angle formed by the direction of travel of the ultraviolet light emitted from the surface light source 62 relative to the first optical axis A1, when the optical axis perpendicular to the emitting surface 65 of the surface light source 62, i.e., the first optical axis A1, is set to 0°. The ultraviolet light emitted from the surface light source 62 that travels at an angle close to the first optical axis A1 is distributed to the lens 67. The ultraviolet light emitted from the surface light source 62 that travels at an angle away from the first optical axis A1 is distributed to the reflecting surface 68a of the reflector 68.

[0108] The boundary between the angle at which ultraviolet light from the surface light source 62 is distributed to lens 67 and the angle at which it is distributed to reflector 68 is defined as the distribution boundary BL. The distribution boundary BL is the boundary at which light is distributed between lens 67 and reflector 68 at the position of the emitting surface 65 of the surface light source 62 located on the optical axis A0 of lens 67. Figure 10 As shown, the position of the emitting surface 65 of the surface light source 62 on the optical axis A0 of the lens 67 is represented by an imaginary line connecting the periphery of the lens 67. The angle of the distribution boundary BL is the angle between the distribution boundary BL and the optical axis A0 of the surface light source 62. In addition, the first optical axis A1 of the surface light source 62 is aligned with the optical axis A0 of the lens 67.

[0109] Let the angle of the allocation boundary BL be θ [°], and the diameter of the lens 67 be Dl [mm]. In this case, Equation 10 below holds. By combining Equation 4 above with Equation 10, the angle θ of the allocation boundary BL is expressed by Equation 11 below. In this embodiment, the diameter of the lens 67 is designed to converge to the maximum size of the paraxial image plane 90 (the length of one side is 70 mm). Therefore, the angle θ of the allocation boundary BL satisfies the relationship expressed by Equation 12 below (where θ ≤ 89).

[0110] tan(θ)=(Dl / 2) / La…(Formula 10)

[0111] θ=arctan{(Dl / 2) / (Li×Wl / (Wi+Wl))}…(Equation 11)

[0112] θ≤arctan(35×(70-Wl) / Li×Wl)…(Equation 12)

[0113] (3-3) First reflector

[0114] The first reflector 70 is supported on the second side plate 31b, which is the other side plate in the left-right direction of the housing 31. The first reflector 70 can be directly supported on the second inner surface 36 of the second side plate 31b, or indirectly supported on the second inner surface 36 of the second side plate 31b via other components (adhesive tape or fasteners). The second inner surface 36 is the surface of the second side plate 31b formed on the side of the airflow path 34. The first reflector 70 is formed as a rectangular plate extending along the second direction. In this embodiment, the first reflector 70 is located above the front side of the indoor fan 42, downstream of the portion of the indoor heat exchanger 50 that is inclined rearward from the lower end.

[0115] The first reflector 70 reflects ultraviolet rays irradiated from the irradiation unit 61 towards one end in the first direction. The first reflector 70 has a first reflective surface 71. When viewed in a cross section along a third direction, the first reflective surface 71 has a curved shape that is concave towards the other end in the first direction. As a result, it is possible to suppress the ultraviolet rays reflected by the first reflective surface 71 from tilting significantly outward in the second direction.

[0116] When viewed in a cross-section along the second direction, the first reflective surface 71 preferably has a curved shape that is concave towards the other end in the first direction. In other words, the first reflective surface 71 is preferably spherical or parabolic in shape. Such a shape of the first reflective surface 71 can suppress the reflected ultraviolet rays from tilting significantly outward in the third direction, i.e., extending towards the direction of travel.

[0117] The first reflecting surface 71 is composed of a concave surface having the aforementioned curved shape. The first reflecting surface 71 includes an irradiated surface 71a that is irradiated by ultraviolet light from the surface light source 62. The irradiated surface 71a is part of the first reflecting surface 71, and therefore is composed of a concave surface. The radius of curvature R1 of the first reflecting surface 71, including the irradiated surface 71a, satisfies the relationship expressed by Equation 13 below.

[0118] 0.5×Li≤R1≤2×Li…(Equation 13)

[0119] The radius of curvature R1 of the first reflecting surface 71 is preferably greater than Li. This is because if the radius of curvature R1 of the first reflecting surface 71 is less than Li, the focal point of the first reflecting surface 71 is too close to the first reflecting part 70, and the ultraviolet rays reflected by the first reflecting surface 71 are significantly tilted outward in the second direction. The radius of curvature R1 of the first reflecting surface 71 is preferably 2 × Li or less. This is because if the radius of curvature R1 of the first reflecting surface 71 is greater than 2 × Li, the ultraviolet rays reflected by the first reflecting surface 71 are too close to the irradiation part 61, which may promote the deterioration of the irradiation part 61 caused by ultraviolet rays.

[0120] The orthoreflectivity r1 of the first reflecting surface 71 is preferably 50% or more. This orthoreflectivity r1 [%] is expressed by the following formula 14.

[0121] r1=(Ea2 / Ea1)×100…(Formula 14)

[0122] Here, Ea1 is the amount of ultraviolet light [mw] entering the first reflector 70. Ea2 is the amount of ultraviolet light [mw] reflected by the first reflector 70.

[0123] (3-4) Second reflector

[0124] The second reflective portion 80 is supported on one side plate of the housing 31 in the left-right direction. The second reflective portion 80 can be directly supported on the side plate of the housing 31, or indirectly supported on the side plate via other components (adhesive tape or fasteners, etc.). The second reflective portion 80 is formed as a rectangular plate extending along the second direction.

[0125] In this embodiment, the second reflector 80 is located above the front side of the indoor fan 42, downstream of the portion of the indoor heat exchanger 50 that is inclined rearward from its upper end. The second reflector 80 is positioned opposite the first reflector 70 across the processing space R. When viewed along the first direction, at least a portion of the first reflector 70 overlaps with the second reflector 80. In this case, the first reflector 70 preferably overlaps entirely with the second reflector 80.

[0126] The second reflector 80 reflects the ultraviolet rays reflected by the first reflector 70 toward the other end in the first direction. The second reflector 80 has a second reflective surface 81. When viewed in a cross-section along a third direction, the second reflective surface 81 has a curved shape that is concave toward one end in the first direction. As a result, it is possible to suppress the ultraviolet rays reflected by the second reflective surface 81 from tilting outwards significantly in the second direction.

[0127] When viewed in a cross-section along the second direction, the second reflective surface 81 preferably has a curved shape that is concave towards the other end in the first direction. In other words, the second reflective surface 81 is preferably spherical or parabolic in shape. Such a shape of the second reflective surface 81 can suppress the reflected ultraviolet rays from tilting significantly outward in the third direction, i.e., extending towards the direction of travel.

[0128] The second reflecting surface 81 is composed of a concave surface having the aforementioned curved shape. The radius of curvature R2 of the second reflecting surface 81 satisfies the relationship expressed by Equation 15 below. The radius of curvature R2 of the second reflecting surface 81 is preferably greater than Li. This is because if the radius of curvature R2 of the second reflecting surface 81 is less than Li, the focal point of the second reflecting surface 81 will be too close to the second reflecting part 80, and the ultraviolet rays reflected by the second reflecting surface 81 will be significantly tilted outward in the second direction.

[0129] 0.5×Li≤R2≤2×Li…(Equation 15)

[0130] The positive reflectivity r2 of the second reflecting surface 81 is preferably 50% or more. This positive reflectivity r2 [%] is expressed by the following formula 16.

[0131] r2 = (Eb2 / Eb1) × 100… (Equation 16)

[0132] Here, Eb1 is the amount of ultraviolet light [mw] entering the second reflector 80. Eb2 is the amount of ultraviolet light [mw] reflected by the second reflector 80.

[0133] (6) Operation of the ultraviolet irradiation device

[0134] In the air conditioner 10, the ultraviolet irradiation device 60 operates during both cooling and heating operations. The ultraviolet irradiation device 60 irradiates ultraviolet light from the irradiation unit 61 toward the processing space R during the operation of the indoor fan 42.

[0135] like Figure 11 As shown, the irradiation unit 61 irradiates ultraviolet light from one end (the side of the first inner surface 35) in the first direction of the processing space R toward the other end (the side of the second inner surface 36). For example, the optical axis of the ultraviolet light from the irradiation unit 61, i.e., the first optical axis A1, is aligned with the first direction. The irradiation unit 61 irradiates ultraviolet light between the two side plates in the left-right direction of the housing 31, thus forming the entire processing space R in the first direction of the indoor heat exchanger 50.

[0136] The ultraviolet rays irradiated from the irradiation unit 61 are reflected by the first reflector 70. The first reflector 70 reflects the ultraviolet rays from one end side (the side of the second inner surface 36) in the first direction of the processing space R toward one end side (the side of the first inner surface 35).

[0137] The optical axis of the ultraviolet rays reflected by the first reflector 70, i.e., the second optical axis A2, is offset by a predetermined first angle θ1 relative to the first optical axis A1 of the irradiation unit 61 in the second direction. Specifically, the second optical axis A2 is offset by a predetermined angle θ1 relative to the first optical axis A1 in the second direction. The first angle θ1 is a predetermined angle greater than 0 degrees. Therefore, the processing space R of the ultraviolet irradiation device 60 can be expanded in the second direction, i.e., the length direction of the fins 51. The ultraviolet rays reflected by the first reflector 70 reach the second reflector 81 from the first reflector surface 71, thus the processing space R, which is expanded in the second direction, can be formed throughout the first direction of the indoor heat exchanger 50. The first angle θ1 is preferably 1° or more.

[0138] The ultraviolet rays reflected by the first reflector 70 are reflected by the second reflector 80. The second reflector 80 reflects the ultraviolet rays from one end side (the side of the first inner surface 35) in the first direction of the processing space R toward the other end side (the side of the second inner surface 36).

[0139] The optical axis of the ultraviolet rays reflected by the second reflector 80, i.e., the third optical axis A3, is offset by a predetermined second angle θ2 relative to the second optical axis A2 of the first reflector 70 in the second direction. Specifically, the third optical axis A3 is offset by a predetermined angle θ2 relative to the second optical axis A2 in the other end of the second direction. The second angle θ2 is a predetermined angle greater than 0°. Therefore, the processing space R of the ultraviolet irradiation device 60 can be expanded in the second direction, i.e., the length direction of the fins 51. The ultraviolet rays reflected by the second reflector 80 reach the first reflector 71 from the second reflector surface 81, thus, the processing space R that expands in the second direction can be integrally formed in the first direction of the indoor heat exchanger 50. The second angle θ2 is preferably 1° or more.

[0140] The first angle θ1 and the second angle θ2 are offset towards the same side (the other end side) in the second direction. Therefore, by means of the first reflector 70 and the second reflector 80, the processing space R can be expanded towards the other end side in the second direction. Furthermore, in Figure 11 In the image, the angles θ1 and θ2 are shown in an exaggerated manner.

[0141] The ultraviolet rays reflected by the second reflector 80 reach the first reflector 70 again. The first reflector 70 reflects the ultraviolet rays in a manner that is offset by a predetermined angle towards the other end in the second direction. The ultraviolet rays reflected by the first reflector 70 reach the second reflector 80 again. The second reflector 80 reflects the ultraviolet rays in a manner that is offset by a predetermined angle towards one end in the second direction. The ultraviolet rays reflected by the second reflector 80 reach the first reflector 70 again. The first reflector 70 reflects the ultraviolet rays in a manner that is offset by a predetermined angle towards one end in the second direction.

[0142] As described above, in the ultraviolet irradiation device 60, ultraviolet light is reflected alternately and repeatedly between the first reflective part 70 and the second reflective part 80.

[0143] -Features of Implementation Method 1-

[0144] In the ultraviolet irradiation apparatus 60 of this embodiment, an irradiation unit 61 is disposed at one end of the processing space R, and a first reflector 70 is disposed at the other end of the processing space R. The irradiation unit 61 concentrates ultraviolet rays emitted from the surface light source 62 toward the first reflector 70 via an optical component OP. The optical component OP generates a paraxial image plane 90 of a light-emitting surface 65 on the irradiated surface 71a of the irradiated ultraviolet rays on the first reflector 70. As a result, the propagation of ultraviolet rays reflected by the irradiated surface 71a of the first reflector 70 in the direction of travel can be suppressed. As a result, ultraviolet rays can be efficiently irradiated onto the air flowing in the processing space R.

[0145] In the ultraviolet irradiation device 60 of this embodiment, the ultraviolet light emitted from the surface light source 62 has a relatively short wavelength of 200 nm or more and 300 nm or less. The shorter the wavelength of the ultraviolet light, the easier it is to refract in the lens 67. Therefore, by using the lens 67, the ultraviolet light emitted from the surface light source 62 can be easily adjusted to form a paraxial image plane 90 on the irradiated surface 71a of the first reflector 70, which generates the luminescent surface 65. Furthermore, the aforementioned relatively short wavelength ultraviolet light is suitable for inactivating viruses and bacteria in the air.

[0146] In the ultraviolet irradiation device 60 of this embodiment, the length of the fourth side 90d (corresponding to the width in a predetermined direction) of the paraxial image plane 90 is 20 nm or more and 70 mm or less. With a paraxial image plane 90 of such size generated on the irradiated surface 71a, the ultraviolet irradiation device 60 can be made into a relatively compact structure. Therefore, the ultraviolet irradiation device 60 can be installed even in the limited space inside existing equipment such as an air conditioner 10.

[0147] In the ultraviolet irradiation apparatus 60 of this embodiment, when the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, i.e., the irradiation distance, is set to Li [mm], and the length of the second side 65b of the emitting surface 65 (equivalent to the maximum width in a specified direction) is set to Wl [mm], the distance La [mm] between the principal point P1 of the lens 67 and the emitting surface 65 satisfies the following relationship: Li×Wl / (70+Wl)≤La≤Li×Wl / (20+Wl). Therefore, a paraxial image plane 90 with a fourth side 90b length of 20 nm or more and 70 mm or less can be generated on the irradiated surface 71a of the first reflector 70.

[0148] In the ultraviolet irradiation apparatus 60 of this embodiment, when the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, i.e., the irradiation distance, is set to Li [mm], and the length of the second side 65b (equivalent to the maximum width in a specified direction) of the emitting surface 65 is set to Wl [mm], the distance Lb [mm] between the vertex P2 of the paraboloid of revolution of the reflector 68a and the emitting surface 65 satisfies the following relationship: Li×Wl / (70-Wl)≤Lb≤Li×Wl / (20-Wl). Therefore, a paraxial image plane 90 with a fourth side 90b length of 20 nm or more and 70 mm or less can be generated on the irradiated surface 71a of the first reflector 70.

[0149] In the ultraviolet irradiation device 60 of this embodiment, when the distance between the emitting surface 65 of the surface light source 62 and the irradiated surface 71a of the first reflector 70, i.e., the irradiation distance, is set to Li [mm], and the length of the second side 65b of the emitting surface 65 (equivalent to the maximum width in a specified direction) is set to Wl [mm], the angle θ [°] at the position of the emitting surface 65 located on the optical axis A0 of the lens 67, which becomes the distribution boundary between the light pair lens 67 and the reflector 68, satisfies the following relationship: θ ≤ arctan(35 × (70 - Wl) / Li × Wl), where θ ≤ 89. Therefore, the diameter of the lens 67 converges to the maximum dimension in the third direction of the paraxial image plane 90, i.e., 70 mm or less. Thus, a relatively small diameter lens 67 can be used to generate a paraxial image plane 90 with a width of 20 nm or more and 70 mm or less in a specified direction on the irradiated surface 71a of the first reflector 70. This is advantageous for realizing the ultraviolet irradiation device 60 with a compact structure.

[0150] In the ultraviolet irradiation apparatus 60 of this embodiment, the radius of curvature R1 of the irradiated surface 71a of the first reflector 70 is greater than 0.5 times the irradiation distance Li and less than 2 times the irradiation distance Li. The irradiated surface 71a having such a radius of curvature R1 allows ultraviolet light irradiated from the irradiation unit 61 to be reflected towards the vicinity of the irradiation unit 61. This makes the ultraviolet irradiation apparatus 60 a compact structure, and it can also be used in relatively narrow processing spaces R.

[0151] In the ultraviolet irradiation apparatus 60 of this embodiment, the second reflector 80 is disposed at one end of the processing space R in a first direction, i.e., the same side as the irradiation unit 61. Ultraviolet rays reflected by the first reflector 70 are reflected again by the second reflector 80 towards the other end in the first direction. This allows the ultraviolet rays emitted from the irradiation unit 61 to be repeatedly reflected between the first reflector 70 and the second reflector 80, enabling them to remain in the processing space for a relatively long time. This is beneficial for efficiently irradiating the air flowing in the processing space R with ultraviolet rays.

[0152] In the ultraviolet irradiation device 60 of this embodiment, the radius of curvature of the first surface 67a of the lens 67 facing the surface light source 62 is greater than the radius of curvature of the second surface 67b facing the first reflector 70. If the radius of curvature of the first surface 67a is greater than that of the second surface 67b, the distance between the principal point P1 of the lens 67 and the surface light source 62 becomes longer, and the magnification of the paraxial image plane 90 becomes smaller. Therefore, it is possible to prevent ultraviolet light irradiated from the irradiation section 61 from leaking from the first reflector 70, while simultaneously constructing the ultraviolet irradiation device 60 compactly.

[0153] In the ultraviolet irradiation device 60 of this embodiment, the first surface 67a and the second surface 67b of the lens 67 are both even-order aspherical surfaces. This reduces aberrations contained in the paraxial image plane 90. This helps to suppress the propagation of ultraviolet rays reflected from the irradiated surface 71a of the first reflector 70 in the direction of travel.

[0154] In the air conditioner 10 of this embodiment, an ultraviolet irradiation device 60 is used. This ultraviolet irradiation device 60 can efficiently irradiate the air flowing in the processing space R with ultraviolet light. Therefore, in the air conditioner 10, ultraviolet light-based inactivation of viruses and bacteria in the air can be effectively performed.

[0155] (Variation example)

[0156] like Figure 12 As shown, the ultraviolet irradiation device 60 can also be positioned upstream of the portion of the indoor heat exchanger 50 that is inclined forward from the upper end than the lower end, in front of the indoor fan 42, and a processing space R is formed along the upstream side (inflow surface) I2 of this portion in the airflow direction. The irradiation section 61 is, for example, positioned near the lower front end of the indoor heat exchanger 50. The irradiation section 61 can also be positioned towards the front of the indoor heat exchanger 50 near the V-shaped portion.

[0157] In this structure, a processing space R is formed on the upper side of the drain tray 43. Therefore, the growth of bacteria in the drain tray 43 can be inhibited. In addition, ultraviolet light is less likely to leak to the outside of the housing 31 through the suction port 32.

[0158] (Other implementation methods)

[0159] Alternatively, other flow path forming components for dividing the airflow path 34 may be provided inside the housing 31. In this case, the flow path forming components inside the housing 31 may form the first inner surface 35 supporting the irradiation part 61, the second inner surface 35 supporting the second reflector 80, and the second inner surface 36 supporting the first reflector 70. The flow path forming component can be any component that forms a surface defining the airflow path 34. For example, the flow path forming component may be a partition plate separating the airflow path 34 from the electrical component compartment, a support plate for the indoor heat exchanger 50, a frame for the drain pan, etc.

[0160] The heat transfer tube 52 can also be a flat, porous tube, rather than a round tube.

[0161] The ultraviolet light emitted from the surface light source 62 can have a wavelength of less than 200 nm or a wavelength of more than 300 nm, as long as it can be expected to inactivate viruses and bacteria in the air.

[0162] The paraxial image plane 90 generated on the irradiated surface 71a of the first reflector 70 is not limited to a square shape; it can also be rectangular, or even round, elliptical, or other shapes corresponding to the shape of the emitting surface 65 of the surface light source 62. Furthermore, the size of the paraxial image plane 90 can be adjusted to accommodate the space required for processing space R when installed in existing equipment such as the air conditioner 10.

[0163] The optical component OP can be just a reflector 68 or just a lens 67, as long as it can focus the ultraviolet rays emitted from the surface light source 62 toward the first reflector 70 and generate the paraxial image plane of the emitting surface 65 of the surface light source 62 on the irradiated surface 71a of the first reflector 70, or it can be other components.

[0164] The control unit C can also irradiate ultraviolet light through the ultraviolet irradiation device 60 when the indoor fan 42 is stopped. In this case, it is possible to suppress the growth of bacteria when the air conditioner 10 is stopped.

[0165] The first reflecting surface 71 of the first reflecting part 70 may also be a planar shape inclined relative to the second direction, and the second reflecting surface 81 of the second reflecting part 80 may also be a planar shape inclined relative to the second direction.

[0166] The ultraviolet irradiation device 60 is not limited to the aforementioned location within the housing 31, but can also be installed in other locations within the housing 31. The ultraviolet irradiation device 60 can also form an ultraviolet processing space R along the outflow and inflow surfaces of the outdoor heat exchanger 22 of the outdoor unit 20.

[0167] The air conditioner 10 can also be an indoor multi-split type with two or more indoor units 30, or an outdoor multi-split type with two or more outdoor units 20. The air conditioner 10 may not be a split type, but rather an integrated type housing a heat exchanger on the side and a heat source side within a single casing. The air conditioner 10 may not be a stationary type. Specifically, the air conditioner 10 can be a container refrigeration unit for cooling the interior space of a transport container, or a vehicle air conditioner.

[0168] The above describes the embodiments and modifications; however, it should be understood that various changes in manner and details can be made without departing from the spirit and scope of the claims. Furthermore, the above embodiments and modifications can be appropriately combined or substituted as long as they do not impair the function of the object of this disclosure.

[0169] The terms “first,” “second,” “third,” etc., used above are used to distinguish the statements to which these statements are given, and there is no limit to the number or order of these statements.

[0170] Industrial availability

[0171] As explained above, this disclosure is useful for ultraviolet irradiation devices and air conditioners.

[0172] Label Explanation

[0173] R processing space

[0174] OP Optical Components

[0175] Principal point of lens P1

[0176] The vertex of the P2 reflecting surface

[0177] 31 shell

[0178] 32 suction port

[0179] 33 blowout

[0180] 34 airflow path

[0181] 60 UV irradiation device

[0182] 61Irradiation Department

[0183] 62 light sources

[0184] 65 luminous surfaces

[0185] 67 lens

[0186] 67a First Page

[0187] 67b Second Page

[0188] 68 reflectors

[0189] 68a reflector

[0190] 70 First Reflector

[0191] 71a Irradiated surface

[0192] 80 Second Reflector

[0193] 90 paraxial image plane

Claims

1. An ultraviolet irradiation device that irradiates an air-flowing processing space (R) with ultraviolet light, wherein, The ultraviolet irradiation device includes: An irradiation unit (61) is disposed at one end of the processing space (R) in a first direction and irradiates ultraviolet light toward the other end of the first direction; and A first reflective part (70), which is disposed at the other end of the processing space (R) in the first direction, reflects the ultraviolet rays irradiated by the irradiation part (61) toward the end side in the first direction. The irradiation unit (61) includes: a surface light source (62) having a light-emitting surface (65) that emits ultraviolet light; and an optical component (OP) that focuses the ultraviolet light emitted from the surface light source (62) toward the first reflective unit (70). The optical component (OP) is configured to generate a paraxial image plane (90) of the emitting surface (65) on the irradiated surface (71a) of the first reflective portion (70) where ultraviolet light is irradiated.

2. The ultraviolet irradiation device according to claim 1, wherein, The irradiation unit (61) has a lens (67) as the optical component (OP), which refracts ultraviolet rays emitted from the surface light source (62). The ultraviolet light emitted from the surface light source (62) has a wavelength of more than 200 nm and less than 300 nm.

3. The ultraviolet irradiation device according to claim 1 or 2, wherein, The width of the paraxial image plane (90) in the specified direction is more than 20 mm and less than 70 mm.

4. The ultraviolet irradiation device according to claim 3, wherein, The irradiation unit (61) has a lens (67) as the optical component (OP), which refracts ultraviolet rays emitted from the surface light source (62). The lens (67) is disposed on the front side of the light-emitting surface (65). When the distance between the emitting surface (65) of the surface light source (62) and the irradiated surface (71a) of the first reflector (70), i.e., the irradiation distance, is set as Li [mm], and the maximum width of the emitting surface (65) in a specified direction is set as Wl [mm], the distance La [mm] between the principal point (P1) of the lens (67) and the emitting surface (65) satisfies the following relationship: Li×Wl / (70+Wl)≤La≤Li×Wl / (20+Wl).

5. The ultraviolet irradiation device according to claim 3 or 4, wherein, The irradiation unit (61) has a reflector (68) as the optical component (OP), which reflects ultraviolet light emitted from the surface light source (62). The reflector (68) is configured to surround the space on the front side of the light-emitting surface (65). The reflective surface (68a) of the reflector (68) that reflects ultraviolet light is a curved surface that is equivalent to or approximately similar to a parabola of revolution. When the irradiation distance between the emitting surface (65) of the surface light source (62) and the irradiated surface (71a) of the first reflector (70) is set as Li [mm], and the maximum width of the emitting surface (65) in a specified direction is set as Wl [mm], the distance Lb [mm] between the vertex (P2) of the paraboloid of revolution of the reflector (68a) and the emitting surface (65) satisfies the following relationship: Li×Wl / (70-Wl)≤Lb≤Li×Wl / (20-Wl).

6. The ultraviolet irradiation device according to any one of claims 3 to 5, wherein, The irradiation unit (61) has a lens (67) and a reflector (68) as optical components (OP). The lens (67) refracts ultraviolet rays emitted from the surface light source (62), and the reflector (68) reflects the ultraviolet rays emitted from the surface light source (62). The lens (67) is disposed on the front side of the light-emitting surface (65). The reflector (68) is configured to surround the space on the front side of the light-emitting surface (65) and the lens (67). When the distance between the light-emitting surface (65) of the surface light source (62) and the irradiated surface (71a) of the first reflector (70), i.e., the irradiation distance, is set to Li [mm], and the maximum width of the light-emitting surface (65) in a specified direction is set to Wl [mm], the angle θ [°] at the position of the light-emitting surface (65) on the optical axis of the lens (67), which becomes the distribution boundary between the light and the lens (67) and the reflector (68), satisfies the following relationship: θ≤arctan(35×(70-Wl) / Li×Wl), where θ≤89.

7. The ultraviolet irradiation device according to any one of claims 1 to 6, wherein, The irradiated surface (71a) is composed of a concave surface with a specified curvature. When the distance between the emitting surface (65) of the surface light source (62) and the irradiated surface (71a) of the first reflector (70), i.e., the irradiation distance, is set to Li [mm], the radius of curvature R1 of the irradiated surface (71a) satisfies the following relationship: 0.5×Li≤R1≤2×Li.

8. The ultraviolet irradiation device according to any one of claims 1 to 7, wherein, The ultraviolet irradiation device includes a second reflector (80) which is disposed at one end of the processing space (R) in the first direction and reflects the ultraviolet rays reflected by the first reflector (70) toward the other end of the first direction.

9. The ultraviolet irradiation device according to any one of claims 1 to 8, wherein, The irradiation unit (61) has a lens (67) as the optical component (OP), which refracts ultraviolet rays emitted from the surface light source (62). The lens (67) is a biconvex lens having a first surface (67a) facing the surface light source (62) and a second surface (67b) facing the first reflector (70), wherein the first surface (67a) and the second surface (67b) are both convex. The radius of curvature of the first surface (67a) is greater than the radius of curvature of the second surface (67b).

10. The ultraviolet irradiation device according to claim 9, wherein, The first surface (67a) and the second surface (67b) are both even-order aspherical surfaces.

11. An air conditioner, comprising: The housing (31) has an air intake (32) for drawing in air, an air outlet (33) for expelling air, and an airflow path (34) extending from the air intake (32) to the air outlet (33); and An ultraviolet irradiation device (60) irradiates a portion of the airflow path (34) as a processing space (R) with ultraviolet light. The ultraviolet irradiation device (60) is the ultraviolet irradiation device (60) according to any one of claims 1 to 10.

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