Onboard-Dampfverwertungssystem mit zweistufigem Ventil

摘要

A liquid-responsive control valve (20,120) for controlling the venting of fuel vapor from a fuel tank (10) to a vapor recovery apparatus (18) in a manner providing a shutoff cue to a person filling the tank. The control valve comprises valve means adapted for venting fuel vapor from the tank to the recovery apparatus at a first higher rate when the fuel level in the tank is below a first level, at a second lower rate when the fuel level in the tank reaches the first level, and for closing when a second higher level is reached.