KR200284240Y1 - Optical air pollution sensor - Google Patents

Abstract

This paper is designed to precisely detect the concentration of a small amount of fine particles suspended in the air by forcibly inhaling air into the sensing device.The optical air pollution enables precise detection of the amount of light scattered from low concentration of fine particles. Regarding the detection device, according to the optical contamination detection device of this paper, a forced circulation method for stably detecting fine particles in the air, and equipped with a resistance heating element (11) for sucking air, and emits light to the fine particles The light emitting unit 9 and the light collecting lenses 12 and 13 to collect light, the light blocking plates 5, 5 ", 6 and 6" inside the apparatus and the matte bottom 20 to detect only the light scattered from the fine particles. And a multi-stage (double) slit structure consisting of first and second double slits 15, 15 ", 16, 16 ". In addition, the voltage obtained by converting the photocurrent signal of the reflected light scattered in the optical air pollution detection apparatus according to the present invention into a voltage (200), amplification (300), filtering (400), comparison, and DC smoothing is applied to the detected particle concentration. Optical air pollution detection device with a built-in control circuit 500 for outputting the analog voltage according to the.

Description

Optical Air Pollution Detection Device {OPTICAL AIR POLLUTION SENSOR}

In the conventional air pollution sensor, in selecting the sensor of the light emitting and receiving part, the selection of expensive laser diodes or limited elements with high directivity and high sensitivity, the supply and sensor characteristics are unstable, so the stability and precision for the practical application It was low, and there was a structural weakness in mounting the sensor only at the position where air on the product was sucked in.

In order to solve the problems of the prior art, this paper is designed to add or change the structure of the machine by applying forced air circulation and applying optical lens and slit for stable and accurate detection of floating dust particles in the air. It is to solve the difficulty of the phase and to accurately detect the small amount and the fine particles.

1 is a block diagram showing the configuration of the air pollution detection device according to the present invention.

Figure 2 is a schematic structural diagram of the air pollution detection device according to the present invention.

3 is a plan view of the apparatus of the air pollution detection device according to the present invention.

Figure 4 is a front view of the mechanism of the air pollution detection device according to the present invention.

<Description of main parts of drawing>

1: control board 2: optical unit case (black box)

3: Inlet 4,4 ": Outlet

5,5 ": Entrance shield plate 6,6": Exit shield plate

7: light receiving unit 8: light receiving element

9 light emitting unit 10 light emitting element

11: resistance heating element 12,13: male light emitting part condenser lens

14,14 ": Case side 15,15": Male and light emitting part 1slit

16,16 ": male and light emitting part 2nd slit 17: detection area

18: Connector 19: Signal output and control device

20: Matte surface (upper case, lower case)

21,22,23: Electromagnetic wave and visible light shielding case (control board, male, emitting side)

24: lens cleaning cover 100: drive part of the light emitting part

200: photoelectric conversion unit 300: signal amplifier

400: Noise cut part 500: Signal voltage output part (peak hold)

Hereinafter, the construction and operation of the optical air pollution detection device according to the present invention will be explained according to the display of the drawings. The lens of the light emitting part 9 in the optical part case 2 which blocks external light and inhales air from the outside is described. And the lenses of the first and second slits and the light receiving part 7 and the first and second slits at a predetermined angle, and under the detection area 17 of the inhaled air, the resistance heating element 11 is provided. The lens cleaning cover 24 and the driving circuit 100 and the light emitting unit 9 for irradiating constant infrared light in the detection area, and the receiving unit 7 of the reflected light received by the reflection of air and the received optical signal. A photoelectric conversion unit 200 for converting an electric signal, a noise filter unit 400 for separating a signal amplified primarily from the amplified unit 300 of the converted signal, and amplifying a final signal voltage from which the noise is removed, Signal voltage output unit 50 for controlling the output proportional to the concentration of dust by outputting 0).

Referring to the operation in the detection of air pollution shown in Figs. 1 and 2, first, the inlet 3 of the outside air is disposed on the upper and lower sides of the two side surfaces 14 and 14 " One place and two places of discharge ports 4, 4 "are formed, respectively, and one location of the intake port 3 and the inside of the discharge ports 4, 4" are provided with light shielding plates 5, 5 "at the suction end. It was installed horizontally, and the light shielding plates 6, 6 " on the discharge port 4, 4 "

Then, between each of the light blocking plates 5, 6 and the opposite light blocking plates 5 ", 6" on one side wall 14 of this optical part case 2 and the other side wall 14 "corresponding thereto. Penetrating through the light-emitting portion 9 having the infrared light emitting diode 10 and the light-receiving portion 7 with the phototransistor 8, respectively, inclined so that the light on the light emitting side is not reflected to the light receiving side under dark conditions. And the light emitting portion 9 and the light receiving portion 7 of the optical portion case 2 in a region where the intersection of the optical axes is narrowed by the line facing the light blocking plates 5, 5 " and (6, 6 "). Intersect each other on the center vertical line.

Then, a power supply and signal terminal box 18 is provided on the control board 1 surface of the optical unit case 2, and a signal control and output unit 19 is provided on the opposite side of the control board 1. .

In the optical air pollution detection device, a resistor 11 having a heating element is provided horizontally on the center vertical line of the device, that is, in the passage of the suction air through the suction port 3.

Subsequently, the detailed operation of the apparatus will be described. First, the terminal box 18 for supplying the power of the safety device generates heat according to the energization of the built-in resistance heating element 11, The surrounding air is warmed by this heating element and creates forced convection into the optics case 2 between the light blocking plates 5, 5 " and 6, 6 "

As a result, the inlet port 3 is in a 負壓 state, which sucks the atmospheric air therein and ascends to the center portion of the optical unit case 2 to create forced air flow toward the outlet ports 4 and 4 ″.

Then, the light emitted from the light emitting element 10 of the light emitting portion 9 is focused and projected by the optical lens 13 with respect to the rising suctioned air, and scattered and reflected air in the air is received by the light receiving portion 7. ) Is optically detected by the light receiving element 8 through the condenser lens 12. In the measurement of the above configuration, the light blocking unit 5, 5 " and 6, 6 " in the optical unit case 2 block the direct sunlight from the inlet and the discharge port, except for the light rays, and the processing apparatus. (19) The shield case portions 21, 22, and 23 for shielding the light receiving portion 7 and the light emitting portion 9 from external electromagnetic noise enable high resolution and clear detection.

In addition, the operation of the processing apparatus 19 installed in the present paper is based on the driving circuit 100, which is the light emitting unit control stage for continuously emitting the light emitting element 10, and the amount of light received by the light receiving element 8 by the operation of the light emitting element. After converting the amount of scattered light incident from the photoelectric conversion unit 200 for converting the photocurrent to a voltage to a voltage, the noise amplified with the signal and the signal amplifier 300 for amplifying the weak signal voltage (visible light region) Since the signal voltage output unit 500 for outputting only the signal passed through the high pass filter 400 to remove the final signal voltage is installed so as to output a voltage proportional to the concentration of the incident dust The detection signal of the processing device 19 is output as a voltage or a current having a value proportional to the concentration of the particulate contamination component.

As described above, according to the optical air pollution detection device of the present invention, it is possible to adopt a general-purpose male and a light emitting element by applying a lens and a slit, and to stabilize a certain amount of light emitted to the detection area 17. Precise detection of external intermittent dust particles due to irradiation of light and the adoption of a heating element resistance 11 for forced convection enables stable detection regardless of the place of the product.

Claims (5)

The condenser lens 13 and two slits 15 and 16 are provided on the path of the light output from the light emitting unit 9 for optically detecting the fine particles of air on the path to the detection area 17. optical air quality detection device, according to the said been disposed detection regions 17 scatter, the condenser lens 12 on to proceed to the light receiving portion (7) of the reflected light and the second portion a slit (15 ", 16") from. The optical air pollution detection device according to claim 1, further comprising a heating element (11) for forced convection provided under the optical part case (2). The shielding part (5, 5 ", 6, 6") for shielding the detection area (17) from external light, and the shield part (21, 22) for shielding the electromagnetic noise of the processing unit (17). And 23) an optical air pollution detection device. The structure according to claim 1, wherein the particles having the dust particles detected therein are immediately discharged by increasing the outlets 4, 4 " of the outflowing air to the inlet 3 of the inflowing air into the optical part case 2. Optical air pollution detection device characterized in that it comprises a. The optical current detected by the light receiving unit 7 in the optical unit case 2 is converted into the photoelectric conversion 200 and the signal amplification 300 and the noise cut 400 and the signal voltage output of the processing unit 19. Optical air pollution detection device characterized in that it has a portion (500).