Air purification device

Abstract

To provide an air cleaner including a light source substrate in which light sources are suitably arranged so that a circular photocatalyst filter can be efficiently irradiated with light.SOLUTION: The air purifier includes a circular photocatalytic filter carrying a photocatalyst, a plurality of light sources configured to emit light for activating the photocatalyst, and light source substrates on which the light sources are mounted, wherein the light source substrates are provided on an upstream side and a downstream side of the photocatalytic filter, respectively, and the light sources mounted on the respective substrates are combined to annularly irradiate a circular first surface and a circular second surface of the photocatalytic filter from respective directions.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an air purifier that uses a photocatalytic filter to sterilize and deodorize. [Background technology]

[0002] Devices have been put into practical use that purify the air that passes through a photocatalytic filter by irradiating it with ultraviolet light or other light to activate the photocatalyst. For example, a sterilization and deodorization device that uses a photocatalytic filter can take in air from around the device, sterilize and deodorize the air as it passes through a photocatalytic filter irradiated with light inside the device, and then discharge the purified air. In addition to reducing odors in living rooms and cars, it is known to be effective in reducing viruses and bacteria.

[0003] Relatively small air purifiers require not only performance aspects such as sterilization and deodorization, but also design and compactness, and power saving is also an important requirement. For example, Patent Document 1 proposes an invention for an air purifier that efficiently irradiates light onto a photocatalytic filter using multiple light irradiation means. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-142138 Summary of the Invention [Problem to be solved by the invention]

[0005] The configuration described in the above-mentioned Patent Document 1 is such that when light sources are provided on the upstream and downstream sides of the air passing through the photocatalytic filter, the parts where the illuminance of the light is highest are made different on the upstream side and the downstream side. As shown in Figure 2 of Patent Document 1, the positions where strip-shaped substrates on which the light sources are mounted are arranged are shifted between the upstream side and the downstream side of the rectangular (oblong) photocatalytic filter.

[0006] However, considering the variety of product shapes, the photocatalytic filter is not limited to a rectangular (oblong) shape. When a circular photocatalytic filter is considered, the configuration described in Patent Document 1 has the following problems. If a rectangular substrate is placed next to a circular photocatalytic filter, the substrate and the irradiation range may extend beyond the photocatalytic filter. Furthermore, it is inefficient to prepare several types of rectangular substrates with different lengths and shapes, each with a light source mounted thereon.

[0007] From a design perspective, it is anticipated that product designs will employ cylindrical housings or place photocatalytic filters in circular spaces inside the housings, so it is necessary to meet the need for circular photocatalytic filters that fit neatly into the circular shape of the housing.

[0008] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an air purifying device equipped with a light source substrate in which light sources are suitably arranged so as to efficiently irradiate a circular photocatalytic filter with light. [Means for solving the problem]

[0009] In order to achieve the above object, one embodiment of the air purifying device of the present invention is an air purifying device that takes in air into its main body by operating a fan and discharges air that has been purified using a photocatalyst, and is characterized in that it has a circular photocatalyst filter that supports the photocatalyst, a plurality of light sources that irradiate light that activates the photocatalyst, and a light source board on which the plurality of light sources are mounted, and the light source boards are provided respectively on the upstream and downstream sides of the airflow passing through the photocatalyst filter, and the plurality of light sources are arranged so that the combination of the light source mounted on the upstream board and the light source mounted on the downstream board annularly irradiates the circular first and second surfaces of the photocatalyst filter from each direction. [Effects of the Invention]

[0010] According to the present invention, it becomes possible to efficiently irradiate a circular photocatalytic filter with light. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a diagram illustrating an air purification device according to an embodiment of the present invention. [Figure 2] This is an example of applying the conventional technology to a circular photocatalytic filter. [Figure 3] 2 shows an example of the configuration of a photocatalytic filter and a light source substrate in the air purifying device according to the present embodiment. [Figure 4] This is an example in which holes that serve as air flow paths are provided in a circular light source substrate. [Figure 5] 10 is an example of a cross-shaped light source substrate. [Figure 6] This is an example in which the positions of light sources are varied on a cross-shaped light source substrate. [Figure 7] This is an example in which light sources with different illumination ranges are used on a cross-shaped light source substrate. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the following embodiments do not limit the invention described in the claims. Furthermore, although multiple technical features are described in the following embodiments, not all of these multiple features are necessarily essential to the present invention and may be used arbitrarily. Furthermore, in the drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0013] 1 is a diagram illustrating an air purifying device according to an embodiment of the present invention, showing a cross-sectional view of the main body. The air purifying device according to an embodiment of the present invention has one or more of a sterilization function for sterilizing the air using a photocatalytic filter, a virus removal function, and a deodorization function for deodorizing the air.

[0014] In Figure 1, the air purifier draws in air from the surrounding area through an inlet 1 and exhausts the purified air through an outlet 2. The air purifier body contains multiple light sources 3 and a substrate 5 (also referred to as a light source substrate) on which the light sources 3 are mounted, with a photocatalytic filter 6 disposed between the pair of substrates 5. The range of light emitted from the light sources 3 is represented by an irradiation range 4. The multiple light sources 3 are provided on a surface of the substrate 5 facing the photocatalytic filter 6, and the multiple light sources 3 are arranged on the substrate 5 so that the light emitted from each light source (multiple irradiation ranges 4) efficiently covers both the first surface (upstream side of the airflow) and the second surface (downstream side of the airflow) of the photocatalytic filter 6.

[0015] The intake of ambient air into the main body of the air purifier in Figure 1 and the exhaust of air from the main body to the outside are made possible by the rotation of fan 7, which is driven by a power source (not shown). Although the example shows fan 7 attached to the upper part of the main body (exhaust side), it may also be attached to the lower part of the main body (intake side). When fan 7 operates to suck in air from around the main body, it is recommended to provide a pre-filter 8 to prevent dust in the air from entering the main body.

[0016] The main body housing 9 has an inner role as a base member for fixing the above-mentioned components, and an outer sheath on the outside. In this embodiment, a cylindrical main body housing 9 having a roughly circular body is assumed, but the shape of the main body housing 9 does not have to be circular or cylindrical as long as the shape of the photocatalytic filter 6 is circular.

[0017] The photocatalytic filter 6 is made of, for example, ceramic, has numerous honeycomb-shaped holes in the direction in which air passes, and is loaded with a titanium oxide (TiO2) photocatalyst. The photocatalytic filter 6 activates the function of the pre-loaded photocatalyst through light emitted by the light source 3, and exerts effects such as sterilization, virus removal, and deodorization on the air it comes into contact with. The light source 3 is connected to a power source (not shown) via printed wiring or cables on the substrate 5, and lights up when power is supplied from the power source. This embodiment uses a photocatalytic filter 6 that uses a photocatalyst that reacts to ultraviolet (UV) light, which has a greater sterilization and deodorization effect than visible-light-reactive photocatalysts, and a light source 3 that emits ultraviolet (UV) light. A light-emitting diode (UV-LED) is used as the light source 3 to miniaturize the product.

[0018] In this embodiment, two sets of photocatalytic filter elements, a first photocatalytic filter element 100 and a second photocatalytic filter element 200, are arranged in series in the air flow path within the main body, with the photocatalytic filter 6 and a pair of substrates 5 arranged before and after it being considered as one set. In this way, the air purified by the first set is further purified by the second set, further improving the sterilization and deodorization performance, and it is expected that cleaner air will be discharged. However, the number of combinations may be three or more sets, or just one set. Furthermore, by continuously operating the fan 7, air exhausted from the main body is again drawn in for repeated sterilization and deodorization, which is expected to reduce bacteria and viruses in the air over time and reduce odor concentration.

[0019] In the air purifying device of FIG. 1, it is desirable that light be efficiently irradiated onto the circular photocatalytic filter 6 by a plurality of light sources 3 suitably arranged on substrates 5 provided before and after the filter.

[0020] Fig. 2 shows an example in which a light source substrate 5a that imitates the strip-shaped substrate described in Patent Document 1, which is a conventional technique, is applied to a circular photocatalytic filter 6. In the example of Fig. 2, the irradiation range of the light source 3 on the photocatalytic filter 6 is different between the upstream surface and the downstream surface (21 indicates the irradiation range from the opposite side), but part of the irradiation range 4 extends beyond the photocatalytic filter 6. In addition, there are areas on the photocatalytic filter 6 where light does not hit (such as the top and bottom in the vertical axis direction of the figure), so there is room for improvement in terms of efficiency.

[0021] FIG. 3 shows an example of the configuration of the photocatalytic filter 6 and light source substrate 5b in the air purifier according to this embodiment. In the example shown in FIG. 3, a circular light source substrate 5b is configured to illuminate the two circular surfaces of the photocatalytic filter 6, and multiple light sources 3 are mounted on each substrate. In FIG. 3, one light source substrate 5b is provided on the upstream side of the air flow relative to the photocatalytic filter 6, and another light source substrate 5b is provided on the downstream side. Five light sources 3 are mounted on the surface of the light source substrate 5b facing the photocatalytic filter 6, at positions corresponding to the vertices of a regular square and the intersections of their diagonals. In FIG. 3, this means that the light sources 3 are mounted on the back side of the substrate at the circle indicated by the dashed line on the light source substrate 5b. Furthermore, the light source substrate 5b on the downstream side of the photocatalytic filter 6 is positioned 45 degrees rotated relative to the light source substrate 5b on the upstream side to shift the phase of the light sources. The two light source substrates 5b position the light sources 3 at each vertex of a roughly regular octagon, and the combination of these light sources forms a ring-shaped illumination range. Light is emitted in a circular pattern from both the upstream and downstream sides, and the light source 3 located near the center of the substrate complements the illumination of the central part of the ring. This improves the efficiency of the light irradiation range on the photocatalytic filter 6. Another advantage is that the same type of light source substrate 5b can be used on the upstream and downstream sides, allowing for the substrate to be shared.

[0022] FIG. 4 shows another example of the configuration of the photocatalytic filter and light source substrate shown in FIG. 3, in which holes serving as air flow paths are provided in a circular light source substrate. In the configuration of light source substrate 5b in FIG. 3, the air flow path is limited to the outer periphery of light source substrate 5b. Therefore, in order to improve the air flow, light source substrate 5c has a shape in which holes serving as air flow paths are provided in a circular light source substrate. As in FIG. 3, the position of light source 3 in light source substrate 5c is located at a position corresponding to the intersection of the vertices of a regular square and its diagonal on the surface of light source substrate 5c facing photocatalytic filter 6. Light source substrate 5c has four holes serving as air flow paths, avoiding the position of light source 3. However, the number, position, size, or shape of the holes are not limited to those shown.

[0023] Light sources 3 are mounted on the backside of the light source substrate 5c at the five dotted-line circular positions shown in Figure 4. Furthermore, the downstream light source substrate 5c is positioned 45 degrees rotated relative to the upstream light source substrate 5c of the photocatalytic filter 6 to shift the phase of the light sources. The two light source substrates 5c position the light sources 3 at each vertex of a roughly regular octagon, and the combination of these light sources forms a ring-shaped illumination range. Light is emitted in a ring-shaped manner from both the upstream and downstream sides, and the light source 3 located near the center of the substrate complements the illumination of the central portion of the ring. This improves the efficiency of the light illumination range on the photocatalytic filter 6. Furthermore, the same type of light source substrate 5c can be used on both the upstream and downstream sides, which has the advantage of allowing for common use of the substrate. Furthermore, the configuration of the light source substrate 5c in Figure 4 allows for the formation of a linear airflow through the holes, making it easier for air to pass through the small holes in the photocatalytic filter 6.

[0024] Fig. 5 shows an example of a cross-shaped light source substrate as another example of the configuration of the photocatalytic filter and light source substrate shown in Fig. 3. Light source substrate 5d is a cross-shaped substrate on which light sources 3 are mounted in order to improve air flow even more than in Fig. 4. The light sources 3 on light source substrate 5d are located near the four tips and the center of the cross on the surface of light source substrate 5d facing the photocatalytic filter 6.

[0025] Light sources 3 are mounted on the backside of the light source substrate 5d at the five dotted-line circle positions in Figure 5. Furthermore, the downstream light source substrate 5d is positioned 45 degrees rotated relative to the upstream light source substrate 5d of the photocatalytic filter 6, shifting the phase of the light sources. The two light source substrates 5d position the light sources 3 at each vertex of a roughly regular octagon, and the combination of these light sources forms a ring-shaped illumination range. Light is emitted in a ring-shaped manner from both the upstream and downstream sides, and the light source 3 located near the center of the substrate complements the illumination of the central part of the ring. This improves the efficiency of the light illumination range for the photocatalytic filter 6. Furthermore, the same type of light source substrate 5d can be used on the upstream and downstream sides, which has the advantage of allowing the substrate to be shared.

[0026] By using a cross-shaped light source substrate 5d as shown in Figure 5, the air passes through the areas other than the substrate, forming a straight-line airflow, which makes it easier for the air to pass through the small holes in the photocatalytic filter 6. Furthermore, using a cross-shaped substrate increases the number of substrates that can be obtained from a material of a given size compared to the circular shapes shown in Figures 3 and 4, thereby reducing component costs. Such a cross-shaped substrate may be one that is produced from a material in a cross shape, or it may be one that is made by combining two linear substrates into a cross shape.

[0027] FIG. 6 is a modified example of the cross-shaped light source substrate shown in FIG. 5, and is an example in which the position of the light source on the light source substrate is different from that in FIG. 5. The light source substrate 5e is a cross-shaped substrate on which light sources 3 are mounted. The light sources 3 are mounted on the back side of the light source substrate 5e at the positions of five circles indicated by dashed lines. Furthermore, as in FIG. 5, the light source substrate 5e on the downstream side of the photocatalytic filter 6 is positioned at a position rotated 45 degrees relative to the light source substrate 5e on the upstream side, thereby shifting the phase of the light source. The two light source substrates 5e place the light sources 3 at each vertex of a substantially regular octagon, and the combination of these light sources forms a ring-shaped illumination range.

[0028] The positions of the light sources 3 on the light source substrate 5e shown in FIG. 6 are located on the surface of the light source substrate 5e facing the photocatalytic filter 6, near the four tips of the cross and slightly shifted laterally from the center of the cross. In FIG. 6, the illumination range of the light source 3 located slightly shifted laterally from the center of the cross is indicated by 22. The illumination range 22 is shifted from the center to differentiate it from the illumination range 22 of the light source substrate 5e, which is rotated 45 degrees and located on the opposite side of the photocatalytic filter 6. While the light source substrates 5c and 5d had unilluminated areas between the illumination range of the central light source and the illumination range of the surrounding light sources, the light source substrate 5e can illuminate a wider area, thereby improving the efficiency of the illumination range for the photocatalytic filter 6. The same type of light source substrate 5e can be used on both the upstream and downstream sides, which has the advantage of allowing the substrate to be shared.

[0029] FIG. 7 is a modified example different from that shown in FIG. 6, and is an example in which light sources with different irradiation ranges are used on the light source substrate. The light source substrate 5f is a cross-shaped substrate on which light sources 3 are mounted. The light sources 3 are mounted on the back side of the light source substrate 5f at the positions of five circles indicated by dashed lines. Furthermore, as in FIG. 5, the light source substrate 5f on the downstream side of the photocatalytic filter 6 is positioned at a position rotated 45 degrees relative to the light source substrate 5f on the upstream side, thereby shifting the phase of the light source. The two light source substrates 5f place the light sources 3 at each vertex of a substantially regular octagon, and the combination of these light sources forms a ring-shaped irradiation range.

[0030] The light sources 3 on the light source substrate 5f shown in FIG. 7 are located near the four tips of the cross and near the center of the cross on the surface of the light source substrate 5f facing the photocatalytic filter 6. The light source substrate 5f differs from the light source substrate 5d shown in FIG. 5 in that a light source with a wide illumination range is used for the light source 3 located near the center of the cross substrate. The illumination range of the central light source 3 is represented by 23. While the light source substrates 5c and 5d had unilluminated areas between the illumination range of the central light source and the illumination range of the surrounding light sources, the light source substrate 5f allows illumination over a wider area, thereby improving the efficiency of the illumination range for the photocatalytic filter 6. The light source substrates 5f can also be the same type on both the upstream and downstream sides, which has the advantage of allowing for common use of the substrate. It is possible to provide a light source 3 with a wide illumination range near the center of the cross on only one of the pair of light source substrates 5f, while the other light source substrate may have no light source 3 near the center of the cross or a light source with a normal illumination range 4.

[0031] As explained above, the circular photocatalytic filter 6 is irradiated in a circular range from multiple light sources 3 mounted on light source substrates located upstream and downstream of the air flow, and another light source 3 is used to illuminate the area near the center, thereby enabling efficient light irradiation. [Explanation of symbols]

[0032] 1 Intake 2 Exhaust 3 light source 4. Irradiation range 5. Substrate 5a Light source board (rectangular) 5b Light source board (circular) 5c Light source substrate (circular with flow channel) 5d light source board (cross shape) 5e Light source substrate (cross-shaped variant) 5f Light source board (cross-shaped variant) 6 Photocatalytic filter 7 Fan 8 Pre-filter 9 Main unit housing 100 First photocatalytic filter part 200 Second photocatalytic filter part

Claims

1. An air purifying device that takes in air into a main body by operating a fan and discharges air that has been purified using a photocatalyst, a circular photocatalytic filter carrying the photocatalyst; a plurality of light sources that irradiate light that activates the photocatalyst; a light source substrate on which the plurality of light sources are mounted; and The light source substrates are provided on the upstream and downstream sides of the airflow passing through the photocatalytic filter, and the plurality of light sources are arranged so that the combination of a light source mounted on the upstream substrate and a light source mounted on the downstream substrate irradiates the circular first and second surfaces of the photocatalytic filter in a circular pattern from each direction.

2. The air purifying device according to claim 1 , wherein the light source substrate is circular.

3. 3. The air purifying device according to claim 2, wherein the light source substrate is a circular substrate having holes formed therein to serve as air flow paths.

4. The air purifying device according to claim 1 , wherein the light source substrate is cross-shaped.

5. 5. The air purifying device according to claim 4, wherein the light source board has light sources disposed near four ends and a center of the cross shape.

6. The air purifying device according to any one of claims 1 to 5, characterized in that the light source boards have different arrangement phases between the light sources mounted on the upstream board and the light sources mounted on the downstream board.

7. 6. The air purifying device according to claim 1, wherein the light source substrate includes the upstream substrate and the downstream substrate rotated 45 degrees relative to the upstream substrate.

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