| 摘要 |
PURPOSE:To measure dust concentration continuously, by forming the flow of gas including dust at a specified speed, projecting light to the dust flow at a right angle, receiving the scattered light from the light projected area, and converting the light into an electric signal. CONSTITUTION:Air including dust is sucked through a sucking hole by a pump 12 into a duct, which is perpendicularly provided in a dust-concentration measuring apparatus. Thus the dust stream having a specified speed is formed. Cylinders 13a and 13b are provided in the duct flow at a right angle. A black box 14 is provided at the opened facing surfaces of the cylinders. In one cylinder 13a, a light source 13, a condenser lens group 16, and an aperture, which shields stray light, are provided. The end part of the other cylinder 13b is made to be a conical trap. Its tip part is connected to an optical fiber 19 through a trap 18, which intermittently cuts the light from the cylinder 13a. The scattered light from the light projected dust area is received by photoelectric converters 20a and 20b, which are provided on the right and left parts of the duct 10. |
