| 摘要 |
PURPOSE:To enable the deterioration of rubber to be accurately decided, by deciding the shock absorbing rubber, which deteriorates causing a propeller to slip, by breaking a slip checker consisting of flexible substance, in case of the screw propeller with the shock absorbing rubber built inside. CONSTITUTION:A screw propeller 1, serving as a propulsive device of outboard engine or the like, mounts shock absorbing rubber 5 inside a propeller boss absorbing a shock when a rock and drifting wood or the like hit the propeller 1 while a ship is in sailing. Here the propeller 1 is equipped with a slip checker 2 which forms its central part in a cord shape consisting of flexible substance. This checker 2 mounts its one end to a thrust receiver 4 mounted being fitted to a propeller shaft 3 while the other end to a housing 1a of the shock absorbing rubber 5 through a holder 6. In this way, the propeller 1, when it generates a slip by deteriorating the shock absorbing rubber 5, excessively extends the checker 2 so as to be broken thus deciding the shock absorbing rubber 5 to be deteriorated by visibly detecting a broken condition of this checker. |
