FUEL EVAPORATION GAS DISCHARGE PREVENTION SYSTEM

• Main Authors: KAMURA HITOSHI, MATSUNAGA HIDEO
• Format: Patent
• Language: English; Japanese
• Published: 07.05.2015
• Subjects: BLASTING; COMBUSTION ENGINES; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MECHANICAL ENGINEERING; SUPPLYING COMBUSTION ENGINES IN GENERAL, WITH COMBUSTIBLEMIXTURES OR CONSTITUENTS THEREOF; WEAPONS

PROBLEM TO BE SOLVED: To detect a malfunction of a canister open/close valve.SOLUTION: A purge valve and a bypass valve (canister open/close valve) are controlled to be opened in the operation of an engine to make the internal pressure of a canister be a negative pressure, and a purge function of the canister is determined to be normal. Thereafter, the bypass valve is controlled to be closed, and a switch valve is temporarily opened to open the canister to the atmosphere. When the internal pressure of the canister then varies by a second predetermined pressure P2 or more, the canister open/close valve is determined that it is in a fixedly opened state. When the internal pressure of the canister does not vary by the second predetermined pressure P2 or more, the canister open/close valve is determined that it is not in the fixedly opened state. 【課題】キャニスタ開閉弁の異常検出を可能にする。【解決手段】エンジンの運転中にパージ弁及びバイパス弁（キャニスタ開閉弁）を開作動制御して、キャニスタの内圧が負圧になりキャニスタのパージ機能が正常であることを判定した後に続けて、バイパス弁を閉作動制御し、切替弁を一時的に開作動してキャニスタを大気開放してから、キャニスタの内圧が第２の所定圧Ｐ2以上変化した場合にキャニスタ開閉弁は開固定状態であり、第２の所定圧Ｐ2以上変化しない場合にはキャニスタ開閉弁は開固定状態でないと判定する。【選択図】図６