Fuel vapor control apparatus

摘要

A fuel vapor control apparatus on a motor vehicle fuel tank including a vapor storage canister, a plurality of vent valves on the fuel tank, a plurality of vapor ducts between the vent valves and the vapor storage canister, a plurality of primary liquid traps, and a secondary liquid trap which cooperates with the primary liquid traps in preventing liquid fuel leaking through the vent valves from reaching and contaminating the vapor storage canister. The primary liquid traps are segments of respective ones of the vapor ducts defining standpipes above corresponding ones of the vent valves when the fuel tank is inclined. The primary liquid traps retain liquid fuel leaking through the vent valves and drain by gravity to the fuel tank when the incline of the fuel tank is reduced to zero. The secondary liquid trap is a secondary tank on the top of the fuel tank interposed between the vapor storage canister and the segments of the vapor ducts defining the standpipes. The secondary tank retains liquid fuel which overflows any one of the standpipes and also drains by gravity to the fuel tank when the incline of the fuel tank is reduced to zero.