Raindrop detection device and weather sensor provided with same

Abstract

A raindrop detection device (20) comprises: a housing part (21), an opening section (21a), a light source section (22a), a light receiving section (22b), a microcontroller (25), a base (24), and a discharge section (26). The opening section (21a) is formed in a top surface (21c) of the housing part (21). The light source section (22a) radiates light toward raindrops that pass through the opening section (21a). The light receiving section (22b) is disposed so as to face the light source section (22a) of the housing part (21) and receives the light radiated from the light source section (22a). The microcontroller (25) detects the raindrops in response to changes in the amount of light received by the light receiving section (22b). The base (24) supports the housing part (21) from below. The discharge section (26) is a gap that is formed between an outer peripheral surface (21d) of the housing part (21) and the base (24), and has a height equal to the total height of a bug that enters via the opening section (21a).

Description

Raindrop detection device and weather sensor equipped with the same

[0001] The present invention relates to a raindrop detection device for measuring rainfall and a weather sensor including the same.

[0002] In recent years, tipping bucket rain gauges have been used to measure rainfall, and the tipping bucket includes a receiver that receives falling rainwater, a filter into which the rainwater received in the receiver drips, and a tipping bucket that tips over to collect the rainwater dripping from the filter. For example, Patent Document 1 discloses a rainfall change rate measurement system that can grasp the state of rainfall in more detail and as quickly as possible, and that can be used to predict and prevent various disasters caused by rainfall.

[0003] Japanese Patent Application Laid-Open No. 2019-2684

[0004] However, the above-mentioned conventional rainfall change rate measurement system has the following problems. That is, in the rainfall change rate measurement system disclosed in the above publication, rainfall is detected by a water quantity quantification unit that quantifies a predetermined amount of rainfall using a tipping bucket. Therefore, with this configuration, it is difficult to detect rainfall in real time.

[0005] To address this issue, raindrop detection devices are being used that detect raindrops passing through a specified detection area and detect rainfall in real time. However, with this configuration, there is a risk that foreign objects such as fallen leaves and insects may enter through the opening through which the raindrops pass, making it difficult to accurately detect rainfall. On the other hand, if the gap between the housing and the base is increased to prevent foreign objects such as insects from leaving, wind may enter through the gap and blow up into the area where raindrops are detected, potentially reducing the accuracy of raindrop detection.

[0006] The object of the present invention is to provide a raindrop detection device and a weather sensor equipped with the same that can effectively discharge foreign matter that has entered through an opening to the outside while ensuring the accuracy of raindrop detection in a device that detects raindrops passing through an opening.

[0007] (Means for Solving the Problem) A raindrop detection device according to a first aspect of the present invention includes a housing, an opening, a light source, a light receiving unit, a raindrop detection unit, a base, and an exhaust unit. The housing has a cylindrical outer circumferential surface and a ceiling surface. The opening is formed on the ceiling surface of the housing. The light source is provided in the housing and emits light toward raindrops passing through the opening. The light receiving unit is positioned opposite the light source in the housing and receives the light emitted from the light source. The raindrop detection unit detects raindrops that pass between the light source and the light receiving unit in accordance with changes in the amount of light received by the light receiving unit. The base supports the housing from below. The exhaust unit is a gap formed between the outer circumferential surface of the housing and the base, and has a height equivalent to the total height of an insect entering through the opening.

[0008] Here, in a device that detects raindrops passing through the interior of a housing from an opening provided in the ceiling surface of the housing to detect the amount of rain, foreign objects such as insects and fallen leaves that have entered through the opening are discharged from a gap (discharge section) formed between the outer peripheral surface of the housing and the base, and having a height equivalent to the total height of the insect that entered through the opening. Here, the total height of the insect means, for example, the height of an insect such as a Japanese beetle from the top surface of the base when it has fallen onto the base. Because it is expected that foreign objects such as fallen leaves will be lower in height from the top surface of the base than the total height of the insect, the size of the discharge section gap is set based on the total height of the insect.

[0009] In raindrop detection devices with an opening on the ceiling surface of the housing through which raindrops pass, a certain amount of opening area is required to allow raindrops to pass through. Therefore, in addition to raindrops, foreign objects such as insects like Japanese beetles and fallen leaves may enter through the opening. Therefore, foreign objects that enter through the opening must be quickly expelled from the housing through the gap between the housing and the base. However, if the gap between the housing and the base is made large, wind entering from the side may cause air to rise into the opening, potentially reducing the accuracy of raindrop detection.

[0010] Therefore, the raindrop detection device of the present invention expels insects and other foreign objects through a gap that is equal to the total height of an insect such as a Japanese mustard beetle, which is assumed to be the tallest of all foreign objects that may enter through the opening. This allows insects, fallen leaves, and other foreign objects that accidentally enter through the opening to be smoothly expelled through the gap between the outer surface of the housing and the base, and minimizes the impact of wind from the side, preventing a decrease in raindrop detection accuracy due to wind blowing up at the opening.

[0011] As a result, in a device for detecting raindrops passing through an opening, it is possible to ensure the accuracy of raindrop detection while effectively expelling foreign matter that has entered through the opening to the outside.

[0012] A raindrop detection device according to a second aspect of the present invention is the raindrop detection device according to the first aspect of the present invention, wherein the discharge section has a gap in the range of 5 to 15 mm, which prevents water from rising up at the opening, ensuring raindrop detection accuracy, while effectively discharging foreign matter such as insects or fallen leaves that have entered through the opening.

[0013] A raindrop detection device according to a third aspect of the present invention is the raindrop detection device according to the first or second aspect of the present invention, wherein the light receiving unit is disposed at a height of 30 mm or more above the surface of the base. This prevents raindrops that pass through the opening and fall onto the surface of the base from bouncing back and blocking part of the light received by the light receiving unit, thereby preventing a decrease in raindrop detection accuracy.

[0014] A raindrop detection device according to a fourth aspect of the present invention is the raindrop detection device according to the first or second aspect of the present invention, wherein the housing further has an inner wall surface that connects the opening to the surface of the base. The light source unit and the light receiving unit are provided at opposing positions on the inner wall surface. This allows the light source unit and the light receiving unit to detect raindrops passing between the light source unit and the light receiving unit.

[0015] A fifth aspect of the present invention relates to the raindrop detection device of the fourth aspect of the present invention, and further includes a raindrop detection area provided inside the inner wall surface between the light source unit and the light receiving unit, thereby enabling detection of raindrops passing through the raindrop detection area formed between the light source unit and the light receiving unit.

[0016] A sixth aspect of the present invention provides a weather sensor that includes the raindrop detection device of the first or second aspect of the present invention and a wind measurement device disposed below the base for detecting the speed and direction of wind passing through a predetermined measurement area. This provides a weather sensor that can effectively discharge foreign matter that has entered through the opening while ensuring raindrop detection accuracy in the raindrop detection device, and can detect wind speed and direction in the wind measurement device.

[0017] (Effects of the Invention) According to the raindrop detection device of the present invention, in a device that detects raindrops passing through an opening, it is possible to ensure the accuracy of raindrop detection while effectively expelling foreign matter that has entered through the opening to the outside.

[0018] 1 is a perspective view showing the configuration of a weather sensor including a wind measurement device according to an embodiment of the present invention; FIG. 2 is a side view of the weather sensor of FIG. 1; FIG. 3 is a cross-sectional view showing the configuration of the upper part of the weather sensor (raindrop detection device) in the cross-sectional view of line A-A in FIG. 3; and FIG. 4 is a cross-sectional view showing the detailed configuration of the raindrop detection device of FIG.

[0019] A raindrop detection device 20 and a weather sensor 1 including the same according to one embodiment of the present invention will be described below with reference to FIGS. 1 to 5. In this embodiment, unnecessary detailed explanations may be omitted. For example, detailed explanations of well-known matters or redundant explanations of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following explanation and to facilitate understanding by those skilled in the art.

[0020] Furthermore, the applicant provides the accompanying drawings and the following description to enable those skilled in the art to fully understand the present invention, and they are not intended to limit the subject matter described in the claims.

[0021] (1) Configuration of the weather sensor 1 The weather sensor 1 according to this embodiment is a device that is installed, for example, outdoors and measures rain, wind, illuminance, temperature, humidity, air pressure, etc., and as shown in Figures 1 and 2, it includes a wind measurement device 10, a raindrop detection device 20, an illuminance meter 30, and a thermo-hygro-barometer 40.

[0022] 1 and 2, the wind measurement device 10 is provided in the middle section of the weather sensor 1 and measures the speed and direction of wind passing through the gap between the raindrop detection device 20 and the thermo-hygro-barometer 40. More specifically, as shown in FIG. 2, the wind measurement device 10 includes ultrasonic sensors 11a, 11b, 11c, and 11d, a base 12, a reflecting surface 13, a column member 14, and a support portion 15.

[0023] As shown in FIG. 1 and other figures, the ultrasonic sensors 11a, 11b, 11c, and 11d are arranged on the upper surface 12a of the base 12. The ultrasonic sensors 11a, 11b, 11c, and 11d are used in pairs (ultrasonic sensors 11a and 11b and ultrasonic sensors 11c and 11d) arranged to face each other. One of the pair of ultrasonic sensors 11a and 11b functions as an emitter that emits ultrasonic waves, and the other functions as a receiver that receives ultrasonic waves. These functions can also be switched in reverse.

[0024] For example, when ultrasonic sensor 11a emits an ultrasonic wave, ultrasonic sensor 11b, which is positioned opposite ultrasonic sensor 11a, receives the ultrasonic wave emitted from ultrasonic sensor 11a and reflected by reflecting surface 13. When ultrasonic sensor 11b emits an ultrasonic wave, ultrasonic sensor 11a, which is positioned opposite ultrasonic sensor 11b, receives the ultrasonic wave emitted from ultrasonic sensor 11b and reflected by reflecting surface 13.

[0025] Similarly, when ultrasonic sensor 11c emits an ultrasonic wave, ultrasonic sensor 11d, which is positioned opposite ultrasonic sensor 11c, receives the ultrasonic wave emitted from ultrasonic sensor 11c and reflected by reflecting surface 13. When ultrasonic sensor 11d emits an ultrasonic wave, ultrasonic sensor 11c, which is positioned opposite ultrasonic sensor 11c, receives the ultrasonic wave emitted from ultrasonic sensor 11d and reflected by reflecting surface 13.

[0026] The pillar members 14 are erected on the upper surface 12a on which the ultrasonic sensors 11a, 11b, 11c, and 11d are arranged, are provided around the wind measurement area, and support the base 24 from below. The support parts 15 are provided on the upper surface 12a on which the ultrasonic sensors 11a, 11b, 11c, and 11d are arranged, and protrude from the upper surface 12a while supporting the ultrasonic sensors 11a, 11b, 11c, and 11d.

[0027] 1 and 2, the raindrop detection device 20 is provided in the upper part of the weather sensor 1, and detects raindrops that pass through a predetermined opening 21a (see FIG. 3, etc.) provided on the top surface of the housing 21. It also detects the size of the detected raindrops and the amount per unit time to calculate the amount of rain. The detailed configuration of the raindrop detection device 20 will be described later.

[0028] 1 and 2, the illuminance meter 30 is provided in the upper part of the weather sensor 1 together with the raindrop detection device 20, and measures illuminance as one piece of weather information. The thermo-hygro-barometer 40 is provided in the lower part of the weather sensor 1, and measures temperature (air temperature), humidity, and air pressure as weather information.

[0029] (2) Configuration of Raindrop Detection Device 20 As shown in FIG. 4 , the raindrop detection device 20 according to this embodiment includes a housing 21, a light source 22 a and a light receiving unit 22 b provided inside the housing 21, legs 23, a base 24, a microcomputer (raindrop detection unit) 25, and a discharge unit 26.

[0030] 4, the housing 21 is a substantially cylindrical member having an opening 21a, an inner wall surface 21b, a ceiling surface 21c, and an outer peripheral surface 21d. The opening 21a is provided approximately in the center of the ceiling surface 21c and is formed to penetrate the interior of the housing 21. The inner wall surface 21b forms the inner wall of the housing 21 at the penetration portion formed by the opening 21a. A light source unit 22a and a light receiving unit 22b are arranged at positions facing each other on the inner wall surface 21b.

[0031] The ceiling surface 21c is a generally disk-shaped portion that forms the ceiling portion of the generally cylindrical housing portion 21, and has an opening 21a in its central portion. The outer peripheral surface 21d is a surface that forms the outer peripheral portion of the generally cylindrical housing portion 21, and a gap (discharge portion 26) of a predetermined size is provided between the lower end of the outer peripheral surface 21d and the base 24.

[0032] 4, the light source unit 22a and the light receiving unit 22b are arranged at positions facing each other on the inner wall surface 21b of the opening 21a. The light source unit 22a is, for example, an LED (Light Emitting Diode), and irradiates infrared light toward the light receiving unit 22b via a collimating lens and a condenser lens (neither of which are shown).

[0033] The light receiving unit 22b is, for example, a photodiode, and is positioned opposite the light source unit 22a. The light receiving unit 22b receives light condensed through a condensing lens (not shown). The light source unit 22a irradiates a raindrop detection area A1 (see FIG. 4) formed between the light source unit 22a and the light receiving unit 22b with light. The presence or absence of raindrops is detected when raindrops block part of the light detected by the light receiving unit 22b, reducing the amount of light received by the light receiving unit 22b.

[0034] The plurality of legs 23 are erected on the upper surface of a base 24, and the raindrop detection device 20 is connected via the legs 23 and the base 24 to the wind measurement device 10 that constitutes the middle part of the weather sensor 1. The base 24 is a substantially disk-shaped member, and supports the housing 21 of the raindrop detection device 20 and the like via the plurality of legs 23 erected on its upper surface 24a.

[0035] As shown in FIG. 4, the microcomputer (raindrop detection unit) 25 is connected to the light source unit 22a and the light receiving unit 22b, and detects raindrops that pass between the light source unit 22a and the light receiving unit 22b in response to changes in the amount of light received by the light receiving unit 22b. The discharge unit 26 has a gap size h1 formed between the outer peripheral surface 21d of the housing unit 21 and the base 24, and this gap size h1 has a height equivalent to the total height of an insect that enters through the opening 21a. The discharge unit 26 has a gap size h1 of, for example, 9 mm (preferably, a gap in the range of 5 to 15 mm).

[0036] 5, foreign matter such as insects or fallen leaves that have entered through the opening 21a of the housing 21 can be smoothly discharged to the outside from the discharge section 26. Furthermore, because the size h1 of the gap in the discharge section 26 is approximately 9 mm, which is the same as the total height of an insect that enters through the opening 21a, wind blowing from the side of the weather sensor 1 can be prevented from entering through the gap in the discharge section 26 and being blown up inside the opening 21a.

[0037] As a result, in the device for detecting raindrops passing through the opening 21 a, foreign matter that has entered through the opening 21 a can be effectively discharged to the outside while ensuring the accuracy of raindrop detection. Here, the light source unit 22 a and the light receiving unit 22 b are disposed at a height h2 from the surface of the base 24 of, for example, 40 mm (preferably, 30 mm or more), as shown in FIG.

[0038] This prevents raindrops that pass through the opening 21a and fall onto the upper surface of the base 24 from bouncing back and blocking part of the light received by the light receiving portion 22b, thereby preventing a decrease in the accuracy of raindrop detection.

[0039] <Major Features> As shown in FIG. 5 , the wind measurement device 10 of this embodiment includes a housing 21, an opening 21a, a light source 22a, a light receiving unit 22b, a microcomputer 25, a base 24, and an exhaust unit 26. The housing 21 has a cylindrical outer circumferential surface 21d and a ceiling surface 21c. The opening 21a is formed on the ceiling surface 21c of the housing 21. The light source 22a is provided in the housing 21 and emits light toward raindrops passing through the opening 21a. The light receiving unit 22b is positioned opposite the light source 22a in the housing 21 and receives the light emitted from the light source 22a. The microcomputer 25 detects raindrops passing between the light source 22a and the light receiving unit 22b in response to changes in the amount of light received by the light receiving unit 22b. The base 24 supports the housing 21 from below. The discharge portion 26 is a gap formed between the outer peripheral surface 21d of the housing portion 21 and the base 24, and has a height equal to the total height of an insect that enters through the opening 21a.

[0040] This allows foreign matter such as insects or fallen leaves that accidentally enter through the opening 21a to be smoothly discharged from the gap between the outer peripheral surface 21d of the housing 21 and the base 24. Furthermore, it is possible to minimize the influence of wind from the side of the weather sensor 1 and prevent a decrease in the accuracy of raindrop detection due to wind blowing up inside the opening 21a. As a result, in a device that detects raindrops passing through the opening 21a, it is possible to ensure the accuracy of raindrop detection while effectively discharging foreign matter that has entered through the opening 21a to the outside.

[0041] [Other Embodiments] While one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit and scope of the invention. (A) In the above embodiment, an example was described in which the size h1 of the gap in the discharge portion 26 was 9 mm, preferably in the range of 5 to 15 mm. However, the present invention is not limited to this. For example, if the insects that are likely to enter through the opening 21 a vary depending on the region, season, etc. in which the weather sensor 1 (raindrop detection device 20) is installed, the size of the gap may be set based on the overall height of the largest insect that may enter, depending on the region, season, etc.

[0042] (B) In the above embodiment, the light source unit 22a and the light receiving unit 22b are disposed at a height of 40 mm, preferably 30 mm or more, above the top surface 24a of the base 24. However, the present invention is not limited to this. For example, if the maximum amount of rainfall per unit time that falls on the opening 21a varies depending on the region, season, etc. in which the weather sensor 1 (raindrop detection device 20) is installed, the height positions of the light source unit and the light receiving unit from the top surface of the base can be set according to the region, season, etc.

[0043] (C) In the above embodiment, the weather sensor 1 is described as including the wind measurement device 10, the illuminance meter 30, and the thermo-hygro-barometer 40 in addition to the raindrop detection device 20. However, the present invention is not limited to this. For example, the devices incorporated into a weather sensor including multiple measurement targets are not limited to the above combination, and may be part of the above device or may be combined with other devices.

[0044] (D) In ​​the above embodiment, the raindrop detection device 20 is described as being incorporated into the weather sensor 1. However, the present invention is not limited to this. For example, the raindrop detection device may be used as a standalone device.

[0045] <Note> The raindrop detection device according to the first invention comprises: a housing having a cylindrical outer circumferential surface and a ceiling surface; an opening formed in the ceiling surface of the housing; a light source provided in the housing and irradiating light toward raindrops passing through the opening; a light receiving unit disposed in the housing opposite the light source unit and receiving the light irradiated from the light source unit; a raindrop detection unit that detects raindrops that have passed between the light source unit and the light receiving unit in accordance with a change in the amount of light received by the light receiving unit; a base supporting the housing from below; and an exhaust unit that is a gap formed between the outer circumferential surface of the housing and the base, the exhaust unit having a height equal to the overall height of an insect entering through the opening.

[0046] A second aspect of the present invention is the raindrop detection device of the first aspect, wherein the discharge section has a gap of 5 to 15 mm.A third aspect of the present invention is the raindrop detection device of the first or second aspect, wherein the light receiving section is disposed at a height of 30 mm or more above the surface of the base section.

[0047] A raindrop detection device according to a fourth invention is the raindrop detection device according to any one of the first to third inventions, wherein the housing further has an inner wall surface that connects the opening to the surface of the base, and the light source unit and the light receiving unit are provided at positions facing each other on the inner wall surface.

[0048] The raindrop detection device according to a fifth aspect of the present invention is the raindrop detection device according to the fourth aspect of the present invention, further comprising a raindrop detection area provided inside the inner wall surface between the light source unit and the light receiving unit. The weather sensor according to a sixth aspect of the present invention comprises the raindrop detection device according to any one of the first to fifth aspects of the present invention, and a wind measurement device disposed below the base unit and configured to detect the speed and direction of wind passing through a predetermined measurement area.

[0049] The raindrop detection device of the present invention is a device that detects raindrops passing through an opening, and has the effect of being able to effectively expel foreign matter that has entered through the opening to the outside while ensuring the accuracy of raindrop detection. Therefore, it can be widely applied to raindrop detection devices installed in weather sensors, etc.

[0050] 1 Weather sensor 10 Wind measurement device 11a, 11b, 11c, 11d Ultrasonic sensor 12 Base 12a Top surface 13 Reflective surface 14 Pillar member 15 Support part 20 Raindrop detection device 21 Housing part 21a Opening 21b Inner wall surface 21c Ceiling surface 21d Outer surface 22a Light source part 22b Light receiving part 23 Leg part 24 Base (base part) 24a Top surface 25 Microcomputer (raindrop detection part) 26 Discharge part 30 Illuminance meter 40 Thermo-hygro-barometer A1 Raindrop detection area h1 Gap size h2 Height

Claims

a light source unit provided in the housing unit and irradiating light toward raindrops passing through the opening; a light receiving unit disposed in a position facing the light source unit on the housing unit and receiving the light irradiated from the light source unit; a raindrop detection unit that detects raindrops that have passed between the light source unit and the light receiving unit in response to a change in the amount of light received by the light receiving unit; a base unit that supports the housing unit from below; and a discharge unit that is a gap formed between the outer circumferential surface of the housing unit and the base unit and has a height equal to the overall height of an insect entering through the opening.

2. The raindrop detection device according to claim 1, wherein the discharge portion has a gap in the range of 5 to 15 mm.

3. A raindrop detection device as claimed in claim 1 or 2, wherein the light receiving portion is disposed at a height of 30 mm or more above the surface of the base portion.

4. A raindrop detection device as described in claim 1 or 2, wherein the housing portion further has an inner wall surface that connects from the opening portion to the surface of the base portion, and the light source portion and the light receiving portion are provided in opposing positions on the inner wall surface.

5. The raindrop detection device according to claim 4, further comprising a raindrop detection area provided inside the inner wall surface and between the light source unit and the light receiving unit.

6. A weather sensor comprising: the raindrop detection device according to claim 1 or 2; and a wind measuring device arranged below the base for detecting the speed and direction of wind passing through a specified measurement area.

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