| 摘要 |
PURPOSE:To prevent leakage of fuel from a fuel tank due to thermal expansion of fuel when the tank is full by providing an air chamber, in which the air is enclosed, being surrounded by the liquid surface in the fuel tank and tank walls and by installing a vent valve mechanism on the top wall of the air chamber. CONSTITUTION:A fuel tank 15 is so formed as partitioning an air chamber 30 that is surrounded by an fuel surface L and tank top wall 15a, while the air chamber 30 is separated from an oil inlet 31 by a wall 15a that is formed by indenting downward a portion of the tank top wall 15a in the vicinity of the inlet 31. A vent valve mechanism 32 is installed on a part of the tank top wall 15a that is situated over the air chamber 30, while an intake valve mechanism 42 is provided in a cap 41, that is used to close tha inlet 31. The vent valve mechanism 32 is provided with a valve body 38 that parts from a valve seat 37, against a spring 39, when the pressure in the air chamber 30 exceeds the specified value. On the other hand, the intake mechanism 42 is provided with an intake valve 50 that opens when the fuel is consumed and the pressure in the tank 15 becomes negative. |
