| 摘要 |
PURPOSE:To protect a damper disposed in a propeller boss from exhaust heat of an engine, by forming a water receiving port to a lower casing or a boss section and introducing water entering into the water receiving port directly to the vicinity of the damper. CONSTITUTION:Exhaust gas from an engine is discharged into water in navigation through an exhaust passage 34, the outer circumference of a propeller shaft housing 12, and a space between the outermost cylinder 32 and an outer cylinder 26 of a boss section 18 of a propeller 16. On the other hand, water entered into water receiving ports 40 disposed on walls on both sides of a lower casing 10 by travel resistance pressure is supplied to the outer circumference of the outer cylinder 26 of the boss section 18 of the propeller 16 through a water passage 42 and an opening end 44. The water has a sufficiently low temperature because it is exposed to exhaust gas from the engine there for the first time so that it cools a damper 24 accommodated in the outer cylinder 26 through the outer cylinder 26 and is discharged into water together with the exhaust gas. |
