SMOKE SENSOR FOR DIESEL ENGINE

摘要

PURPOSE:To measure a density of black smoke, which is flowed in an exhaust gas duct, without the influence of sticking carbon by utilizing a degree of attenuation of transmission microwaves which are absorbed and attenuated with fine carbon particles in exhaust gas. CONSTITUTION:A smoke sensor 1 has a metallic cylinder part 11, and the cylinder part 11 is connected to an exhaust gas duct G by flange parts provided in both aperture ends of the cylinder part 11 to constitute a part of the duct. In the cylinder part 11, two metallic plates 12 and 13 are provided to face each other in parallel with the flow of exhaust gas. Center conductors 14a and 15a extended from coaxial contacting plugs 14 and 15 provided on the wall of the cylinder part 11 are connected to both end parts of the metallic plate 12. The metallic plate 13 is connected to and supported on the wall of the cylinder part 11 by metallic bars 16a and 16b in both end parts of the metallic plate 13. A coaxial cable 41 extending to a microwave transmitter 2 is connected to the plug 14, and a coaxial cable 42 extending to a microwave detector 3 is connected to the plug 15.