发明授权
- 专利标题: Leakage determination system for evaporative fuel processing system
- 专利标题(中): 蒸发燃料处理系统泄漏测定系统
-
申请号: US09874036申请日: 2001-06-06
-
公开(公告)号: US06761058B2公开(公告)日: 2004-07-13
- 发明人: Takashi Yamaguchi , Takashi Isobe
- 申请人: Takashi Yamaguchi , Takashi Isobe
- 优先权: JP2000-171837 20000608; JP2000-171838 20000608
- 主分类号: G01M304
- IPC分类号: G01M304
摘要:
There is provided a leakage determination system for an evaporative fuel processing system, which, even when pressure within the evaporative fuel processing system is temporarily increased e.g. due to an increase in the amount of generation of evaporative fuel in a fuel tank, is capable of performing an accurate leakage determination by eliminating the influence of the temporary rise in the pressure within the evaporative fuel processing system on the leakage determination. A pressure sensor detects pressure within the evaporative fuel processing system. Negative pressure is introduced from the intake system into the evaporative fuel processing system, whereby the pressure within the evaporative fuel processing system is reduced until the detected pressure becomes equal to a predetermined negative pressure. After the pressure reduction, the negative pressure is introduced from the intake system into the evaporative fuel processing system under predetermined conditions. Whether or not there is a leak in the evaporative fuel processing system is determined based on a state of the pressure within the evaporative fuel processing system, which has been detected during the introduction of the negative pressure from the intake system.