Gas leakage detection and fail-safe control method for gas-fueled internal combustion engine and apparatus for implementing the same

• Main Authors: Maekawa, Masahiro, Aki, Takahiro, Igarashi, Kohei, Matsuoka, Hiroki
• Format: Patent
• Language: English
• Published: 22.10.2002

1. Field of the Invention A method and apparatus is provided that can detect even small amounts of gas leakage and can perform a proper fail-safe operation when gas leakage is detected. When an engine is stopped and a gas shut-off valve is closed, the amount of decrease of gas pressure is calculated by comparing initial gas pressure with the gas pressure detected after the elapse of a prescribed time, to detect gas leakage. In one embodiment, gas leakage is detected by calculating the accumulated value of the amount of decrease of gas pressure each time the engine is stopped. In another embodiment, gas leakage is detected by calculating the rate of decrease of gas pressure from the initial gas pressure to the gas pressure detected after the elapse of a prescribed time. In a further embodiment, gas leakage is detected by calculating the accumulated value of the rate of decrease of gas pressure each time the engine is stopped. Further, when gas leakage is detected, the gas shut-off valve is closed and a warning is issued.