| 摘要 |
PURPOSE:To transmit alarm when the liquid level abnormally lowers by installing a temperature sensor at the part which is lower by a prescribed level from the liquid level in the cylinder head of an engine which executes evaporative cooling and generates heat when exposed from the liquid surface. CONSTITUTION:In the cylinder head 21 of an engine which executes evaporative cooling, the liquid level is controlled within the control amplitude as shown by the arrow in the figure around a set level l1 in the normal operation. A temperature sensor whose one edge is fixed onto the seat part 24 of an exhaust port wall 23 is installed at the height at a prescribed level l2 below the min. side control amplitude of the set level l1. When the liquid level lowers abnormally to reach a prescribed level l2, the temperature of the exhaust-port wall 23 rises sharply, since the contact with the water having a large heat capacity reduces, and a temperature sensor 25 detects the temperature rise and generates alarm. |
