CN216394804U

CN216394804U - Ultraviolet sterilization device

Info

Publication number: CN216394804U
Application number: CN202122609639.8U
Authority: CN
Inventors: 森冈心平
Original assignee: Enplas Corp
Current assignee: Enplas Corp
Priority date: 2020-10-30
Filing date: 2021-10-28
Publication date: 2022-04-29
Anticipated expiration: 2031-10-28
Also published as: JP2022072989A

Abstract

The present invention relates to an ultraviolet sterilizer. The ultraviolet sterilizer of the present invention comprises: a plurality of light sources for emitting ultraviolet rays; and one or more diffusion members disposed above the plurality of light sources, for diffusing the ultraviolet rays emitted from the plurality of light sources. The illuminance of ultraviolet light on a virtual plane as a sterilization target was 1mW/cm²～3mW/cm²On the opposite side of the diffusion member from the plurality of light sources, at a distance from the light emitting surfaces of the plurality of light sourcesThe diffusion member is configured to maximally diffuse light near an optical axis including light along the optical axis, among light emitted from the light source.

Description

Ultraviolet sterilization device

Technical Field

The present invention relates to an ultraviolet sterilizer.

Background

As a cause of nosocomial infections in hospitals, it is known that bacteria, viruses, and the like (hereinafter, also referred to as "bacteria") attached to soles of medical staff and wheels of service carts spread. For such nosocomial infections, ground mats soaked with drugs are used for sterilization. However, in the sterilization method using a floor mat soaked with a chemical, there is a possibility that the chemical may corrode the floor. Further, the medicine adhering to and remaining in the shoe sole may spread the non-dead bacteria. On the other hand, bacterial inactivation is generally performed by irradiating Ultraviolet C-wave (Ultraviolet C; UVC). However, UVC is known to have a bad influence on the retina of a human body and the like, and safety standards are established for UVC irradiation. As a device for sterilizing a sole or a wheel of a service cart, a sterilization device that is fitted into a floor is known (for example, see patent document 1).

Patent document 1 describes a sterilization apparatus disposed on a floor. The sterilization apparatus described in patent document 1 includes: a plurality of LEDs emitting ultraviolet rays, and a grid dividing the LEDs. In the sterilizer described in patent document 1, the grid prevents transmission of the ultraviolet rays emitted from the LED, and the ultraviolet rays are irradiated to a predetermined region.

However, in the sterilizer disclosed in patent document 1, LEDs are used as light sources for emitting ultraviolet rays, and there is a possibility that the LEDs have directivity, which may adversely affect the human body. On the other hand, if an LED that emits ultraviolet light with a small amount of light is used, sterilization may not be possible.

Documents of the prior art

Patent document

Patent document 1: specification of us patent No. 10117958.

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

Accordingly, an object of the present invention is to provide an ultraviolet sterilizer capable of appropriately performing sterilization while ensuring safety.

Means for solving the problems

In order to achieve the above object, an ultraviolet sterilizer according to an embodiment of the present invention includes: a plurality of light sources for emitting ultraviolet rays; and one or more diffusion members disposed above the plurality of light sources, for diffusing the ultraviolet rays emitted from the plurality of light sources to irradiate ultraviolet rays onto a virtual plane to be sterilizedThe degree is 1mW/cm²～3mW/cm²The diffusion member diffuses light near an optical axis including light along the optical axis among light emitted from the light sources to the maximum.

In the ultraviolet sterilizer according to an embodiment, the diffusion member may be a plurality of diffusion lenses which are disposed corresponding to the plurality of light sources, and each of the diffusion lenses may include an incident surface on which ultraviolet rays are incident and an emission surface from which ultraviolet rays incident from the incident surface are emitted.

According to the ultraviolet sterilizer of one embodiment, a half-value angle of the ultraviolet rays emitted from the light source and diffused by the diffusion member may be in a range of 45 ° to 65 °.

According to an embodiment, the ultraviolet sterilizer may further include a cover that is disposed on a side opposite to the light source with respect to the diffusion member and transmits the ultraviolet rays diffused by the diffusion member.

According to the ultraviolet sterilizer of one embodiment, when the maximum illuminance on the virtual plane of the ultraviolet light emitted from one of the plurality of light sources is 1, the relative illuminance of the ultraviolet light on the virtual plane may be in the range of 0.75 to 1.25.

In the ultraviolet sterilizer according to one embodiment, the illuminance of the ultraviolet light may be an illuminance on a virtual plane to be sterilized, the virtual plane being disposed at a position 25mm away from the light emitting surfaces of the plurality of light sources.

Effect of the utility model

The ultraviolet sterilizer of the present invention can appropriately sterilize, for example, soles of shoes or wheels of service carts while ensuring safety.

Drawings

FIGS. 1A and 1B are views showing the structure of an ultraviolet sterilizer according to embodiment 1 of the present invention,

FIGS. 2A to 2D are views showing the structure of a diffusion member in an ultraviolet sterilizer according to embodiment 1 of the present invention,

FIG. 3 is a graph showing the illuminance distribution of ultraviolet rays on a virtual plane,

FIG. 4 is a graph showing the relationship between the irradiation time of ultraviolet rays and the distance from the light emitting surface of the light source,

FIGS. 5A to 5D are views showing the structure of a diffusion member in an ultraviolet sterilizer according to embodiment 2 of the present invention, and

fig. 6A and 6B are graphs showing the illuminance distribution of ultraviolet light on a virtual plane.

Description of the reference numerals

100: an ultraviolet sterilization device;

110: a light source;

120. 320, and (3) respectively: a diffusion member;

130: a substrate;

140: a cover;

202. 402, a step of: a back side;

204. 404: a recess;

210. 410: an incident surface;

220. 420: an exit surface;

221. 421: a first exit surface;

222. 422: a second exit surface;

230: a flange;

240: a foot part.

Detailed Description

Hereinafter, an ultraviolet sterilizer according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[ embodiment 1]

(Structure of ultraviolet ray sterilization apparatus)

Fig. 1A and 1B are diagrams showing the configuration of an ultraviolet sterilizer according to embodiment 1 of the present invention. Fig. 1A is a plan view of the ultraviolet sterilizer, and fig. 1B is a schematic sectional view taken along line a-a shown in fig. 1A. In fig. 1B, the distance between the light sources (diffusion members) is shown to be short.

As shown in fig. 1A and 1B, the ultraviolet sterilizer 100 includes: a plurality of light sources 110, and a diffusion member 120. The ultraviolet sterilization apparatus 100 may have a substrate 130 and a cover 140 in addition to the plurality of light sources 110 and the diffusion member 120. The ultraviolet sterilizer 100 of the present embodiment includes: a substrate 130, a plurality of light sources 110, a plurality of diffusion members 120, and a cover 140.

The ultraviolet sterilizer 100 of the present embodiment can be used in a state of being embedded in a floor or a wall. By embedding the ultraviolet sterilizer 100 in the floor or wall, the feet or the wheels of the cart do not come into contact with each other, and thus, the safety can be improved and the space can be saved.

The substrate 130 supports the light source 110. In the present embodiment, since the diffusion member 120 is a diffusion lens, the substrate 130 supports the light source 110 and the diffusion member 120. The material of the substrate 130 is not particularly limited as long as the above-described function can be exerted. The substrate 130 may have a circular, elliptical, or rectangular shape in plan view. In the present embodiment, the planar shape of the substrate 130 is a rectangle (rectangle). The thickness and size of the substrate 130 are not particularly limited.

The plurality of light sources 110 emit ultraviolet rays. The type of the light source 110 is not particularly limited as long as it can emit ultraviolet rays. Examples of the light source 110 include a Light Emitting Diode (LED), a mercury lamp, a metal halide lamp, a xenon lamp, and a Laser Diode (LD). The center wavelength or peak wavelength of the ultraviolet light emitted from the light source 110 is preferably 200nm or more and 350nm or less, and more preferably 250nm or more and 290nm or less, from the viewpoint of sterilization efficiency. That is, more preferably, the ultraviolet rays are ultraviolet C-waves (UVC). In the ultraviolet sterilizer 100 of the present embodiment, the plurality of light sources 110 are disposed on the substrate 130. The configuration of the plurality of light sources 110 is not particularly limited. The plurality of light sources 110 may be arranged in a triangular lattice shape or in a rectangular lattice shape, but preferably in a triangular lattice shape. In the present embodiment, the plurality of light sources 110 are arranged in a triangular lattice shape. When the plurality of light sources 110 are arranged in a triangular lattice shape, the distance between the optical axes OA of two adjacent light sources 110 (the length of one side of an equilateral triangle) is not particularly limited, and is, for example, in the range of 52mm to 73 mm. The arrangement of the light sources 110 and the distance between the two adjacent optical axes OA are not particularly limited, and may be appropriately selected according to the light distribution characteristics obtained by the light emitted from the diffusion member 120.

The diffusion member 120 is a member disposed above the plurality of light sources 110 to diffuse the ultraviolet rays emitted from the plurality of light sources 110. Specifically, the diffusion member 120 controls the ultraviolet rays emitted from the light source 110 so that the angle of the ultraviolet rays with respect to the optical axis OA of the light source 110 is increased. The type of material constituting the diffusion member 120 is not particularly limited as long as it can transmit ultraviolet rays and is not easily degraded by ultraviolet rays, but a material having a high ultraviolet ray transmittance is preferable. As examples of the material of the diffusion member 120, there are included: light-transmitting resins such as silicone resin, polymethyl methacrylate (PMMA), Polycarbonate (PC), and epoxy resin (EP), and glass. The structure of the diffusion member 120 is not particularly limited as long as the above-described function can be exerted. As examples of the diffusion member 120, a diffusion lens and a diffusion plate are included. For example, the diffusion lens is disposed on one light source 110 (e.g., a light emitting diode), and diffuses and transmits light emitted from the light source 110. The diffusion plate is, for example, ground glass disposed above the plurality of light sources 110, and diffuses and transmits light emitted from the plurality of light sources 110. In the present embodiment, the diffusion member 120 is a diffusion lens. When the diffusion member 120 is ground glass, the diffusion member 120 is supported by, for example, a housing of the ultraviolet sterilizer 100. On the other hand, in the case where the diffusion member 120 is a diffusion lens, the diffusion member 120 is supported by, for example, the substrate 130. Next, a diffusion lens as the diffusion member 120 will be described.

Fig. 2A to 2D are diagrams showing the structure of the diffusion member (diffusion lens) 120 in the ultraviolet sterilizer 100 according to the present embodiment. Fig. 2A is a top view, fig. 2B is a bottom view, fig. 2C is a front view, and fig. 2D is a cross-sectional view taken along line a-a shown in fig. 2A of the diffusion member 120.

The diffusion member (diffusion lens) 120 has an incident surface 210 and an exit surface 220. The diffusion member 120 may have a flange 230, a leg portion 240, and the like in addition to the incident surface 210 and the exit surface 220. As shown in fig. 2A to 2D, the diffusion member 120 of the present embodiment includes an incident surface 210, an emission surface 220, a flange 230, and a plurality of leg portions 240.

The diffusion member 120 is disposed above the light sources 110. Preferably, the diffusion member 120 is disposed such that the central axis CA of the diffusion member 120 coincides with the optical axis OA of the light source 110 (refer to fig. 1B). The top view shape of the diffusion member 120 is not particularly limited. The diffusion member 120 may have a circular shape in plan view or a substantially rectangular shape with an R-chamfer. In the present embodiment, the diffusion member 120 has a circular shape in plan view.

The incident surface 210 is a surface that is disposed to face the light source 110 and on which ultraviolet rays emitted from the light source 110 are incident. The shape of the incident surface 210 is not particularly limited as long as the above-described function can be exerted. The shape of the incident surface 210 may be the same as the inner surface of the recess or may be a flat surface. In the present embodiment, the incident surface 210 is an inner surface of the recess 204 formed in the back surface 202. The incident surface 210 is disposed in the central portion of the rear surface 202 so as to intersect the central axis CA of the diffusion member 120 (the optical axis OA of the light source 110). The incident surface 210 controls the traveling direction of most of the ultraviolet rays emitted from the light source 110, and causes most of the ultraviolet rays to enter the diffusion member 120. The incident surface 210 intersects the central axis CA of the diffusion member 120 and is circularly symmetric about the central axis CA as a rotation axis.

The emission surface 220 is a surface that emits ultraviolet rays, which are incident from the incident surface 210 and travel inside the diffusion member 120, to the outside. In the present embodiment, the emission surface 220 includes: a first emission surface 221 located within a predetermined range centered on the central axis CA; and a second emission surface 222 formed continuously with the first emission surface 221 around the first emission surface 221. The first emission surface 221 is a curved surface protruding toward the rear surface side. Second emission surface 222 is a smooth curved surface that is located around first emission surface 221 and is convex toward the front surface side. The planar shape of the emission surface 220 is not particularly limited. The planar shape of the emission surface 220 may be circular or substantially rectangular with an R-chamfer. In the present embodiment, the planar shape of the emission surface 220 is substantially rectangular with an R-chamfer. The light emitted from the light source 110 and reaching the first emission surface 221 is diffused and emitted from the first emission surface 221. The light emitted from the light source 110 and reaching the inside of the second emission surface 222 is diffused and emitted by the second emission surface 222, and the light reaching the outside of the second emission surface 222 is condensed and emitted by the second emission surface 222.

The flange 230 is a part for facilitating the operation of the diffusion member 120. The flange 230 is disposed at a position (outer edge portion of the diffusion member 120) farther from the central axis CA than the rear surface 202 and the emission surface 220.

The plurality of leg portions 240 form a gap for releasing heat emitted from the light source 110 to the outside, and are positioned and fixed with respect to the substrate 130. In the present embodiment, the plurality of leg portions 240 are disposed on the rear surface 202 at equal intervals. The number of leg parts 240 is not particularly limited. In the present embodiment, the number of leg portions 240 is three.

The diffusion member (diffusion lens) 120 controls the light distribution of the light emitted from the light source 110 so that the illuminance of the ultraviolet light on the virtual plane to be sterilized is 1mW/cm²～3mW/cm²Within the range of (1). The diffusion member 120 diffuses light near the optical axis including light along the optical axis, among the light emitted from the light source, most. Preferably, the following kinds of light sources and the structure of the diffusion member (diffusion lens) 120 are selected: the type of the light source and the structure of the diffusion member diffusion lens 120 can be set such that the half-value angle of the ultraviolet rays emitted from the plurality of light sources 110 and diffused by the diffusion member 120 is in the range of 45 ° to 65 °. In the case where the half-value angle is less than 45 °, the amount of light toward the direction along the optical axis OA is too large, and there is a possibility that safety to a human body is lowered. On the other hand, if the half-value angle exceeds 65 °, the amount of ultraviolet rays reaching the surface of the cover 140 decreases, and the irradiation time of ultraviolet rays required for sufficient sterilization may become longer.

The cover 140 protects the diffusion member 120 and the light sources 110 and transmits ultraviolet rays emitted from the light sources 110. Preferably, the transmittance of the cover 140 is high. Further, the cover 140 preferably has a predetermined strength because it is stepped on by a person or a cart is placed thereon. The material of the cover 140 is not particularly limited as long as the above-described function can be exerted. As an example of the material of the cover 140, synthetic quartz glass is included.

The distance between the light emitting surface of the light source 110 and the surface of the cover 140 is appropriately set according to the intensity of the ultraviolet rays emitted from the light source 110. Preferably, the distance between the light emitting surface of the light source 110 and the surface of the cover 140 is in the range of 10mm to 100 mm. In the case where the distance is less than 10mm, the lower surface of the cover 140 may contact the diffusion member 120. On the other hand, when the distance exceeds 100mm, the amount of ultraviolet light reaching the surface of the cover 140 decreases, and therefore, the irradiation time of ultraviolet light required to obtain a predetermined amount of ultraviolet light may become long.

Further, the ultraviolet sterilizer 100 may be configured to turn on and off the light source 110 in a contact manner or a non-contact manner. For example, when the ultraviolet sterilizer 100 is disposed on a floor and is in contact with the floor, the power source is automatically turned on and the light source 110 is turned on when the ultraviolet sterilizer 100 is placed thereon; when the ultraviolet sterilizer 100 is removed, the power source is automatically turned off and the light source 110 is turned off. In addition, when the ultraviolet sterilizer 100 is disposed on the floor and is in a non-contact type, the power can be switched on and off without directly contacting the ultraviolet sterilizer 100 by suspending a hand or the like above the ultraviolet sterilizer 100.

(light distribution characteristics of ultraviolet ray sterilizer)

Fig. 3 is a graph showing the illuminance distribution of ultraviolet light on a virtual plane when the three light sources 110 are turned on. The vertical axis in fig. 3 represents the relative illuminance when the maximum illuminance at which one light source 110 is turned on the virtual plane is 1. The horizontal axis of fig. 3 indicates the position on the virtual plane where the ultraviolet light reaches. The broken line, the one-dot chain line, and the two-dot chain line in fig. 3 respectively indicate the relative illuminance at each point on the virtual plane of each light source; the solid line represents the total value of the relative illuminance at each point on the virtual plane.

As shown in fig. 3, the ultraviolet rays emitted from the light source 110 at a relatively small emission angle are controlled so as to be diffused by the first emission surface 221 and directed toward the central portion of the irradiated region formed on the surface of the cover 140 (the region near the central axis CA of the diffusion member 120). Thus, the ultraviolet rays emitted from the light source 110 uniformly irradiate the central portion of the surface of the cover 140 without generating an excessively bright portion in the central portion of the surface of the cover 140. On the other hand, the ultraviolet rays emitted from the light source 110 at a large emission angle are controlled to be condensed and directed toward the end of the irradiation region. Thus, the ultraviolet rays having a large emission angle emitted from the light source 110 are controlled so as to be irradiated to the end portion of the irradiated region to be illuminated by the emitted light of each lamp, and when the irradiated region irradiated by the emitted light of the adjacent light source 110 overlaps with the end portion, the brightness of the end portion is controlled to be the same as the brightness of the central portion of the irradiated region.

As shown in fig. 3, when the maximum illuminance on the virtual plane of the ultraviolet light emitted from one light source 110 of the plurality of light sources 110 is 1, the relative illuminance of the ultraviolet light on the virtual plane is preferably in the range of 0.75 to 1.25, and more preferably in the range of 0.80 to 1.20. By setting the contrast of the ultraviolet rays on the virtual plane within the above range, when the object to be sterilized comes into contact with the surface of the cover 140, it is possible to appropriately sterilize the object. At this time, the illuminance of ultraviolet light on the surface (virtual plane) of the cover 140 was 1mW/cm²～3mW/cm²Within the range of (1). Thus, the illuminance of ultraviolet light was set to 1mW/cm²～3mW/cm²Can be sterilized properly while ensuring safety. Here, the region on the virtual plane, which is the target of determining whether or not the relative illuminance of ultraviolet light satisfies the above condition, is a region corresponding to a region surrounded by the plurality of light sources arranged outermost among the plurality of light sources 110. Therefore, for example, the illuminance of ultraviolet rays at an area located more outside than the light source 110 disposed at the outermost side may be lower than 1mW/cm²。

(simulation of illuminance of ultraviolet ray on virtual plane)

Here, the illuminance of ultraviolet light on a virtual plane was simulated. As the light source, an LED (NCSU 334A; Nissan chemical industries, Ltd.) having a peak wavelength of 280nm and a half-value angle of 40 ℃ was used. In the case of using the diffusion member, the above-described diffusion lens (transmittance 90%) is used. The half-value angle of the ultraviolet rays emitted from the diffusion member was 50 °. The calculation was performed assuming that the ultraviolet light emitted from the light source was spread in a conical shape at a half-value angle and the illuminance of the ultraviolet light on the virtual plane was the maximum illuminance and was uniformly irradiated. The transmittance of the cover was set to 100%.

In the absence of the diffusion member, the illuminance of ultraviolet light on a virtual plane 25mm from the light emitting surface of the light source was 3.97mW/cm². It is known that the dose of ultraviolet radiation required for 99.9% inactivation of Escherichia coli (Escherichia coli NBRC3972) is 9.8mJ/cm². From this result, it was found that the irradiation time of ultraviolet ray required for inactivating E.coli under the above conditions was 9.8 (mJ/cm)²)/3.97(mW/cm²) About 2.5 (sec).

In the case of the ultraviolet sterilizer having the diffusion member, that is, in the ultraviolet sterilizer of the present embodiment, the illuminance of the ultraviolet light on a virtual plane 25mm from the light emitting surface of the light source is 1.75mW/cm². From this, it was found that the irradiation time of ultraviolet ray required for inactivating E.coli was 9.8 (mJ/cm)²)/1.75(mW/cm²) About 5.6 (sec). Therefore, it is found that the irradiation time of the ultraviolet ray required for inactivating escherichia coli is longer than that in the case where the diffusion member is not provided, but escherichia coli in the shoe sole can be sufficiently inactivated by stopping the ultraviolet sterilizer for 5 to 6 seconds or by moving the ultraviolet sterilizer for 5 to 6 seconds while being larger.

Here, the following is specified: in the near ultraviolet spectrum region (wavelength of 200-315 nm, 280nm in the present description), when 8 hours is set as one period, the radiation of ultraviolet rays to the unprotected skin or eyes in the one period should not exceed 3.4mJ/cm²(1 second at 3.4 mW).

Thus, to hairThe half-value angle and the ultraviolet ray irradiation amount of the optical device (a single light source in the case of no diffusion member, or a combination of a light source and a diffusion member in the case of a diffusion member) were 3.4mJ/cm²The relationship between the irradiation times of ultraviolet rays of (1) was investigated. Fig. 4 is a graph showing a relationship between a half-value angle of the light-emitting device and a required irradiation time of ultraviolet rays. In FIG. 4, the horizontal axis represents the distance from the light emitting surface of the light source, and the vertical axis represents the ultraviolet irradiation dose of 3.4mJ/cm²The ultraviolet ray irradiation time of (4). Note that the solid line indicates the result when the half-value angle of the light-emitting device is 40 ° (without the diffusion member), the broken line indicates the result when the half-value angle of the light-emitting device is 50 °, the one-dot chain line indicates the result when the half-value angle of the light-emitting device is 60 °, and the two-dot chain line indicates the result when the half-value angle of the light-emitting device is 80 °.

The position 100cm from the light emitting surface of the light source is approximately the height of eyes when a child aged 5 stands. When the half-value angle of the light-emitting device is 40 °, the illuminance of the ultraviolet ray at that position is 3.4mJ/cm²The irradiation time of ultraviolet ray of (2) is 1367 seconds, whereas 3064 seconds is given when the half-value angle of the light-emitting device is 50 °. In addition, the position 50cm from the light emitting surface of the light source is approximately the height of eyes when a child aged 5 squats to pick up things on the floor. When the half-value angle of the light-emitting device is 40 °, the illuminance of the ultraviolet ray at that position is 3.4mJ/cm²The ultraviolet irradiation time of (2) is 341 seconds, whereas 766 seconds is used when the half-value angle of the light-emitting device is 50 °. In addition, a position 10cm from the light emitting surface of the light source was approximately the height of eyes when a child aged 5 lying on the floor and leaning on the elbow. When the half-value angle of the light-emitting device is 40 °, the illuminance of the ultraviolet ray at that position is 3.4mJ/cm²The irradiation time of ultraviolet ray of (2) is 13 seconds, whereas it is 30 seconds when the half-value angle of the light emitting device is 50 °.

As shown in fig. 4, if the diffusion member is arranged and the half-value angle is 50 °, escherichia coli in the shoe sole (not more than 25mm from the light emitting surface of the light source) can be sterilized in 5.6 seconds. In addition, for human body, even when fallingIn the event of a fall, it is safe if it is within 30 seconds. In addition, it is safe for a child aged 5 years to stand on the ultraviolet sterilizer for about 50 minutes. Further, if the height of the eye is 110cm, it is safe within about 1 hour. The illuminance of ultraviolet light in the state where the diffusion member was disposed (half-value angle of 50 °) was 3.4mJ/cm, as compared with the state where the diffusion member was not disposed (half-value angle of 40 °)²The irradiation time of the ultraviolet ray of (2) is about twice. On the other hand, when a diffusion member having a half-value angle of 80 ° was disposed, the illuminance of ultraviolet light was 3.4mJ/cm²The ultraviolet ray irradiation time of (2) becomes very long, and therefore, it is not suitable for use in a sterilization apparatus. Accordingly, it is preferable that the illuminance of ultraviolet light on a virtual plane 25mm from the light emitting surface of the light source is 1mW/cm²～3mW/cm²In the method of (1), a light source of a predetermined intensity is selected together with a diffusion member having a predetermined half-value angle, and a distance between a light-emitting surface of the light source and a virtual plane is set.

(Effect)

As described above, according to the present invention, the illuminance of ultraviolet light on the virtual plane is set to 1mW/cm²～3mW/cm²Can be sterilized appropriately while ensuring safety.

[ embodiment 2]

(Structure of ultraviolet ray sterilization apparatus)

The ultraviolet sterilizer of the present embodiment is different from the ultraviolet sterilizer 100 of embodiment 1 in the configuration of the diffusion member 320. Therefore, in the present embodiment, the structure of the diffusion member 320 will be mainly described.

Fig. 5A to 5D are diagrams showing the structure of the diffusion member (diffusion lens) 320 in the ultraviolet sterilizer 100 according to the present embodiment. Fig. 5A is a top view of the diffusion member 320, fig. 5B is a bottom view, fig. 5C is a front view, and fig. 5D is a cross-sectional view taken along line a-a shown in fig. 5A.

As shown in fig. 5A to 5D, the diffusion member 320 has an incident surface 210 and an exit surface 420. The diffusion member 320 may have the flange 230, the leg portion 240, and the like in addition to the incident surface 410 and the exit surface 420. As shown in fig. 5A to 5D, the diffusion member 320 of the present embodiment includes an incident surface 410, an exit surface 420, a flange 230, and a plurality of leg portions 240.

The incident surface 410 is a surface that is disposed to face the light source 110 and on which ultraviolet rays emitted from the light source 110 are incident. The shape of the incident surface 410 is not particularly limited as long as the above-described function can be exerted. The shape of the incident surface 410 may be the same as the inner surface of the recess 404 or may be a flat surface. In the present embodiment, the incident surface 410 is an inner surface of the recess 404 formed in the rear surface 202. The incident surface 410 is disposed in the central portion of the rear surface 402 so as to intersect the central axis CA of the diffusion member 320 (the optical axis OA of the light source 110). The incident surface 410 intersects the central axis CA of the diffusion member 320, and is circularly symmetric about the central axis CA as a rotation axis.

The emission surface 420 is a surface that emits ultraviolet rays, which are incident from the incident surface 410 and travel inside the diffusion member 320, to the outside. In the present embodiment, the emission surface 420 includes: first emission surface 421 located within a predetermined range centered on central axis CA; and a second emission surface 422 formed continuously with the first emission surface 421 around the first emission surface 421. The first exit surface 421 is a plane. Second emission surface 422 is a smooth curved surface that is located around first emission surface 421 and is convex toward the front surface side. The planar shape of the emission surface 420 is not particularly limited. The planar shape of the emission surface 420 may be circular or substantially rectangular with an R-chamfer. In the present embodiment, the planar shape of the emission surface 420 is circular.

(light distribution characteristics of ultraviolet ray sterilizer)

Fig. 6A and 6B are graphs showing the illuminance distribution of ultraviolet light on a virtual plane. Fig. 6A shows an illuminance distribution when three light sources 110 are turned on, and fig. 6B shows an illuminance distribution when five light sources 110 are turned on. The vertical axes in fig. 6A and 6B represent relative illuminance when the maximum illuminance at which one light source 110 is turned on the virtual plane is 1. The horizontal axes in fig. 6A and 6B indicate the positions on the virtual plane where the ultraviolet rays reach. The broken line, the one-dot chain line, and the two-dot chain line in fig. 6A respectively indicate the relative illuminance at each point on the virtual plane of each light source: the solid line represents the total value of the relative illuminance at each point on the virtual plane. The short dashed line, the ordinary dashed line, the long dashed line, the one-dot chain line, and the two-dot chain line in fig. 6B respectively indicate the relative illuminance at each point on the virtual plane of each light source; the solid line represents the total value of the relative illuminance at each point on the virtual plane.

As shown in fig. 6A and 6B, the ultraviolet rays emitted from the light source 110 at a relatively small emission angle are controlled so as to be diffused by the first emission surface 421 and directed toward the central portion of the irradiated region formed on the surface of the cover 140 (the region near the central axis CA of the diffusion member 320). Thus, the ultraviolet rays emitted from the light source 110 uniformly irradiate the central portion of the surface of the cover 140 without generating an excessively bright portion in the central portion of the surface of the cover 140. On the other hand, the ultraviolet rays emitted from the light source 110 at a large emission angle are controlled to be condensed and directed toward the end of the irradiation region. Thus, the ultraviolet rays having a large emission angle emitted from the light source 110 are controlled so as to be irradiated to the end portion of the irradiated region to be illuminated by the emitted light of each lamp, and when the irradiated region irradiated by the emitted light of the adjacent light source 110 overlaps with the end portion, the brightness of the end portion is controlled to be the same as the brightness of the central portion of the irradiated region.

As shown in fig. 6A and 6B, when the maximum illuminance on a virtual plane of the ultraviolet light emitted from one light source 110 of the plurality of light sources 110 is 1, the relative illuminance of the ultraviolet light on the virtual plane is preferably in the range of 0.75 to 1.25, and more preferably in the range of 0.80 to 1.20. By setting the contrast of the ultraviolet rays on the virtual plane within the above range, when the object to be sterilized comes into contact with the surface of the cover 140, it is possible to appropriately sterilize the object. At this time, the illuminance of ultraviolet light on the surface (virtual plane) of the cover 140 was 1mW/cm²～3mW/cm²Within the range of (1). Thus, the illuminance of ultraviolet light was set to 1mW/cm²～3mW/cm²Can be sterilized properly while ensuring safety. Here, whether or not the relative illuminance for ultraviolet light in the region on the virtual plane satisfiesThe region to be determined under the above conditions is a region corresponding to a region surrounded by a plurality of light sources arranged outermost among the plurality of light sources 110. Therefore, for example, the illuminance of ultraviolet rays at an area located more outside than the light source 110 disposed at the outermost side may be lower than 1mW/cm²。

Thus, even if the planar shape of the emission surface 420 is circular, the illuminance of ultraviolet light on the virtual plane can be set to 1mW/cm²～3mW/cm²。

(Effect)

As described above, according to the present invention, the same effects as those of embodiment 1 can be obtained.

Industrial applicability

The ultraviolet sterilizer of the present invention can be used in places requiring sterilization, such as hospitals and clinics.

Claims

1. An ultraviolet sterilizer comprising:

a plurality of light sources for emitting ultraviolet rays; and

one or more diffusion members disposed above the plurality of light sources and configured to diffuse the ultraviolet rays emitted from the plurality of light sources,

the illuminance of ultraviolet light on a virtual plane as a sterilization target was 1mW/cm²～3mW/cm²On the opposite side of the diffusion member from the plurality of light sources, and is spaced apart from the light emitting surfaces of the plurality of light sources,

the diffusion member diffuses light near an optical axis including light along the optical axis, of light emitted from the light source, the most.

2. The ultraviolet sterilization apparatus as set forth in claim 1,

the diffusion member is a plurality of diffusion lenses which are arranged corresponding to the plurality of light sources, and each of the diffusion lenses includes an incident surface on which ultraviolet light is incident and an emission surface from which ultraviolet light incident from the incident surface is emitted.

3. The ultraviolet sterilization apparatus as set forth in claim 1,

the half-value angle of the ultraviolet rays emitted from the light source and diffused by the diffusion member is in the range of 45 DEG to 65 deg.

4. The ultraviolet sterilization apparatus as set forth in claim 1,

the ultraviolet sterilizer further includes a cover that is disposed on a side opposite to the light source with respect to the diffusion member and transmits the ultraviolet rays diffused by the diffusion member.

5. The ultraviolet sterilization apparatus as set forth in claim 1,

when the maximum illuminance on the virtual plane of the ultraviolet light emitted from one of the plurality of light sources is 1, the relative illuminance of the ultraviolet light on the virtual plane is in the range of 0.75 to 1.25.

6. The ultraviolet sterilization apparatus as set forth in claim 1,

the illuminance of the ultraviolet light is an illuminance on a virtual plane as a sterilization target, and the virtual plane is disposed at a position 25mm away from the light emitting surfaces of the plurality of light sources.