JPH058487U - Snowfall sensor with illuminance detector - Google Patents

Abstract

(57) [Summary] (Corrected) [Purpose] This plan can prevent malfunction due to external light,
It is an object of the present invention to provide a snowfall sensor with an illuminance detector that can operate only when the snowfall conditions are met and can prevent malfunctions and improve the functions of the snowfall sensor. [Structure] A condenser lens 3 and an infrared light projecting lens 6 are attached to a lens holder 1, and a phototransistor 2 for receiving and receiving infrared snowflakes and an infrared light emitting diode 4 are attached on the opposite sides of the respective lenses. Light emitting diode 4 and phototransistor 2 for receiving and reflecting infrared snowflakes
The printed circuit board 9 is connected to each electrode of
Condensing lens 3 and infrared projection lens 6 of lens holder 1
The phototransistor 5 for detecting illuminance is arranged in the middle of the above, and the front surface thereof is covered with the transparent acrylic or glass 7, and the front surface of the condenser lens 3 can easily pass a certain infrared wavelength and other wavelengths. A difficult infrared filter 11 was inserted between the condenser lens 3 and a panel of transparent acrylic or glass 7.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

  The present invention relates to a snowfall sensor with an illuminance detector.

[0002]

[Prior art]

  Conventionally, this kind of thing is as follows.   1. A light emitting diode that emits infrared rays of a specific wavelength is incorporated into an electric oscillation circuit to generate light. Light and radiate in the air.   2. Infrared infrared radiation is transmitted through a lens and emitted in the spatial range of a specific infrared wavelength. make.   3. A condenser lens that radiates to an object that passes through a spatial region of a specific infrared wavelength and reflects the reflected light Collect in.   4. A phototransistor with high wavelength sensitivity for specific infrared rays is used to receive the electrical amplification The DC voltage amplified in the path is taken out as a signal.

[0003]

[Problems to be solved by the device]

  The conventional techniques described above have the following problems.   1. If an object that passes through the spatial region of a specific infrared wavelength is an object that reflects light, Reflects regardless of the object.   2. It receives street lights, car lights, etc. that contain specific infrared wavelengths.   3. Receives sunlight reflected by building glass windows and walls.

[0004]   The present application has been made in view of such problems of the conventional technology. The purpose of is to provide something that can: is there.   As a condition for detecting snowfall in the winter period, firstly the temperature condition of the atmosphere is Second, it is very close to the freezing temperature, and secondly, the snow cloud that has enough water is trying to detect. The condition that it covers the sky is required.   Only if the above conditions are met, make sure that the performance of the snow detector can be demonstrated. It is necessary to   It is a condition when infrared rays are used to detect snowflakes day and night. Generally, when using infrared reflection, in order to collect the reflected light efficiently, It is a general idea to make the luminous flux stronger.   That is, the intensity of light is inversely proportional to the square of the distance. If is weak, the light can reach a small distance and the reflected light becomes extremely weak. .   The infrared snowfall detector efficiently collects this extremely weak reflected light to provide a signal of snowfall. In order to take out well, it is necessary to increase the sensitivity to the maximum.   However, if the light-receiving sensitivity of the snowfall sensor is increased, it will be It causes the operation.   Therefore, operate the sensor only when the brightness of the space, which is the condition of snowfall, and the illuminance are below. You can do it.   The sensitivity is maximized by using the illuminance detector that can detect a certain brightness. It is possible.

[0005]

[Means for Solving the Problems]

  In order to achieve the above object, the present invention is as follows.   That is, in the case of the present application, the lens holder 1 arranged in the frame 8 has a condenser lens. 3 and infrared projection lens 6 are attached to the opposite side of each lens. Infrared snowflake reflection phototransistor 2 and infrared light emitting diode 4 are attached The infrared light emitting diode 4 and the infrared phototransistor 2 for reflecting and receiving snowflakes. The printed circuit board 9 is connected to each electrode, and the condenser lens of the lens holder 1 is connected. The illuminance detection phototransistor 5 is arranged between the lens 3 and the infrared projection lens 6, The front of them is covered with transparent acrylic or glass 7, and the front of the condenser lens 3 is Infrared filter 1 that allows certain infrared wavelengths to pass easily and other wavelengths to not pass easily Illuminance detection with 1 inserted between the condenser lens 3 and the panel of transparent acrylic or glass 7 It is a snowfall sensor with a device.   In this case, the infrared filter 11 can easily pass a specific infrared wavelength, Wavelengths can be difficult to pass.

[0006]

【Example】

  Examples will be described with reference to the drawings.   B is the snowfall sensor with illuminance detector of this proposal.   Place the lens holder 1 in the frame 8 as shown in FIG. The optical lens 3 and the infrared projection lens 6 are attached respectively, and on the opposite side of each lens Infrared snowflake reflection phototransistor 2 and infrared light emitting diode Install 4.   Infrared light emitting diode 4 and that of phototransistor 2 for receiving and receiving infrared snowflakes A printed circuit board 9 is attached to each electrode.   In addition, the illuminance is set between the condenser lens 3 of the lens holder 1 and the infrared projection lens 6. The phototransistors 5 for detection are arranged, and their front surface is protected from dust, rain, snow in the atmosphere. Cover with clear acrylic or glass 7 to prevent throat.   At that time, a specific infrared wavelength easily passes through the front surface of the condenser lens 3, and other wavelengths pass through. Infrared filter 11 that is hard to pass through is condensed lens 3 and transparent acrylic or glass 7 Insert between panels.

In the figure, 10 is a shielded cable that connects the phototransistor 5 for detecting illuminance and the printed board 9, and is R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ , _{R 9, R 10, R 11} , R 12, R 13, R 14, R 15, R 16, R 17, R 18, R 19 each represent a carbon film _{resistor, C 1, C 2, C} 3, C ₄ is an electrolytic capacitor, IC ₁ and IC ₃ are amplifiers, IC ₂ and IC ₄ are voltage comparators, IC ₅ is NOR gate circuit integrator, and Q ₁ , Q ₂ , Q ₃ and Q ₄ are NPN type. A transistor, B is a thermistor element for detecting the outside air temperature, C is a phototransistor for receiving and receiving infrared snowflakes, and VR is a variable resistor.

[0008]   The operation of the snowfall sensor with the illuminance detector having the above-described components will be described.   DC voltage is applied from the oscillation circuit on the printed circuit board 9 to the cathode of the infrared light emitting diode 4. When a specific modulation pulse is applied to the cathode, the infrared light emitting diode 4 It emits infrared modulated light and is emitted into the air through an infrared projection lens.   In addition, the phototransistor 5 for illuminance detection is connected to the It is connected to the amplifier circuit shown in FIG.   Now, when the brightness of the space is equal to or higher than the brightness of the snowfall condition, the increase on the printed circuit board 9 The output of the width circuit forces the circuit of the phototransistor 2 for receiving and receiving infrared snowflakes. The input can be ignored by turning it off.   On the contrary, the brightness of the space where snowfall is to be detected is less than the brightness of the snowfall condition. In the case of, the reflected light reflected by the snowflakes passes through the condenser lens 3 and the lens holder 1 It is taken out as an electric signal by the amplifier circuit inside.

Next, details of the illuminance sensor will be described. As shown in the circuit diagram, the collector of the illuminance detection phototransistor A is connected to the virtual ground of the amplifier IC ₁ to amplify the voltage generated in the base, which is proportional to the brightness of the space. The brightness of the space under the snowfall condition can be detected by operating the voltage comparator IC ₂ with the voltage at the point S in the circuit diagram as the reference voltage and adjusting the reference voltage at the point S.

[0010]

[Effect of device]

  Since the present invention is configured as described above, it has the following effects.   1. Malfunction due to external light can be prevented.   2. Since it operates only when the snowfall conditions are met, malfunctions can be prevented.   3. The function of the snowfall sensor is improved.   4. Energy saving such as system (road heating) using snowfall sensor Play the role of

[Brief description of drawings]

FIG. 1 is a front view of a snowfall sensor with an illuminance detector.

FIG. 2 is a sectional view taken along line XX.

FIG. 3 is an amplifier circuit diagram.

[Explanation of symbols]

B Snowfall sensor with illuminance detector 1 Lens holder 2 Phototransistor 3 for receiving and receiving infrared snowflakes 3 Focusing lens 4 Infrared light emitting diode 5 Phototransistor 6 for illuminance detection Infrared light projecting lens 7 Transparent acrylic or glass 8 Frame 9 Printed circuit board 10 shielded cable 11 infrared filter R ₁ carbon film resistor R ₂ carbon film resistor R ₃ carbon film resistor R ₄ carbon film resistor R ₅ carbon film resistor R ₆ carbon film resistor R ₇ carbon film resistor R ₈ Carbon film resistor R ₉ Carbon film resistor R ₁₀ Carbon film resistor R ₁₁ Carbon film resistor R ₁₂ Carbon film resistor R ₁₃ Carbon film resistor R ₁₄ Carbon film resistor R ₁₅ Carbon film resistor R ₁₆ Carbon film Resistor R ₁₇ Carbon film resistor R ₁₈ Carbon film resistor R ₁₉ Carbon film resistor C ₁ Electrolytic capacitor C ₂ Electrolytic capacitor C ₃ Electrolytic capacitor C ₄ Electrolytic capacitor IC ₁ Amplifier IC ₃ Amplifier IC ₂ Voltage comparator IC ₄ Voltage comparator IC ₅ NOR gate circuit integrator Q ₁ NPN transistor Q ₂ NPN transistor Q ₃ NPN transistor Q ₄ NPN transistor A Illuminance detection phototransistor B Ambient temperature Detection thermistor element C Phototransistor VR for receiving and reflecting infrared snowflakes VR Variable resistor

Claims (3)

[Scope of utility model registration request] 1. A condenser lens (3) and an infrared light projecting lens (6) are attached to a lens holder (1) arranged in a frame (8), and infrared rays are respectively attached to the opposite sides of the lenses. Phototransistor for receiving and reflecting snowflakes (2)
And an infrared light emitting diode (4) are attached, and a printed circuit board (9) is connected to each electrode of the infrared light emitting diode (4) and the infrared photocatalyst for reflecting and receiving snowflakes (2), and a lens holder. An illuminance detection phototransistor (5) is arranged between the condenser lens (3) and the infrared projection lens (6) of (1), and a transparent acrylic or glass (7) is placed on the front surface of the phototransistor (5). , An infrared filter (11) that allows a certain infrared wavelength to easily pass through the front surface of the condenser lens (3) and hardly transmits other wavelengths is inserted between the condenser lens (3) and a panel of transparent acrylic or glass (7). A snowfall sensor with an illuminance detector characterized in that 2. When a pulse wave modulated at a specific frequency is applied to the cathode of the infrared light emitting diode, the infrared light emitting diode becomes infrared modulated light and is radiated into the air, and an illuminance detecting phototransistor. (5) is connected to the amplification circuit on the printed circuit board (9) by the shielded cable (10), so that when the brightness of the space is equal to or higher than the brightness of the snowfall condition, the amplification on the printed circuit board (9) is performed. As for the output of the circuit, the circuit of the phototransistor (2) for receiving and receiving infrared snowflakes can be forcibly turned off, and the input can be ignored. Conversely, the brightness of the space where snowfall is to be detected is When the brightness is less than the condition, the reflected light reflected by the snowflakes passes through the condenser lens (3), is amplified by the amplifier circuit in the lens holder (1), and then is applied to the infrared light emitting diode. It is taken out as an electric signal in synchronism with the wave, while the collector of the illuminance detection phototransistor (A) is connected to the virtual ground of the amplifier (IC ₁ ),
By amplifying the change in the minute voltage proportional to the brightness of the space generated in the base, using the voltage at the S point as the reference voltage, and operating the voltage comparator (IC ₂ ) to adjust the reference voltage at the S point. The snowfall sensor with an illuminance detector according to claim 1, wherein the snowfall sensor is configured to be able to detect the brightness of the space, which is a snowfall condition. 3. The snowfall sensor with an illuminance detector according to claim 1 or 2, wherein the infrared filter (11) allows a specific infrared wavelength to pass therethrough and hardly passes other wavelengths.