Connection of automobile fuel tank to atmosphere to release tank over pressure

摘要

The fuel tank comprises a chamber (24) with a lower orifice (26) in communication with the tank and an upper orifice (30) in communication through a pipe (28) with the atmosphere. Inside the chamber is a first movable tubular body (32) closed at its upper end and open at its lower end so as to form a float. In the event of reversal of the vehicle this float seals the upper orifice. A second movable ball (58) seals the lower orifice when the vehicle is horizontally at rest. The ball valve is opened by an over pressure in the tank or by vibrations generated during movement of the vehicle and connects the tank to atmosphere.