| 摘要 |
PURPOSE:To easily stretch at an end of an exhaust cylinder a net material which prevents the generation of discharging sparks, entering of foreign substance such as leaves, and blocking of a smooth exhausting due to a nest built by birds. CONSTITUTION:A toroidal protrusion part 8, which emerges from an outer periphery and whose inner diameter R' is larger than an inner diameter R of the exhaust cylinder, is formed in a position where a net material for an exhaust cylinder is to be stretched. A net material 9, formed in a circle whose diameter is slightly larger than the inner diameter R' of a toroidal recess 8', is bent into the shape of a concave lens or other crown shape to fit it in the toroidal recess. This permits the net material 9 to be firmly secured, facilitates replacement thereof, and permits the prevention of corrosion of the exhaust cylinder as well. |
