| 摘要 |
PURPOSE:To improve the breather function against positive and negative pressures in the tank and also to improve the sealing function against abnormal liquid pressure that will be applied to a valve mechanism, by forming the captioned filler cap of an automobile, etc. into an upper chamber and a lower chamber devided by a diaphragm valve and a disk. CONSTITUTION:If there is abnormal positive pressure in the tank, though the disk 6 and the diaphragm valve 5 will be elevated, the elevation of the disk 6 will be restricted by a stopper 7, so that a gap will be formed between the disk 6 and the diaphragm valve 5 to communicate the upper and lower chambers 9, 8 with each other, and the pressure in the tank 22 will be released outside of the tank 22 through the lower chamber 9, venting holes 16, a valve hole 11, the upper chamber 8 and a venting hole 2. If the pressure is negative, the disk 6 and the diaphragm 5 act reversely to communicate the upper and lower chambers 8, 9 with each other to introdue the atmospheric air. If abnormal liquid pressure acts on the valve mechanism 4, the diaphragm 5 will be elevated fully, and therefore the upper end of a valve mouth 11 will be closed by the under surface of the cap body 1 to prevent the fuel from leakage. |
