Abstract: A filler pipe unit for the fuel tank of a motor vehicle includes a substantially rigid fuel inlet pipe having a first end connectable to the vehicle body and a second end for connection to the fuel tank. A vent pipe connected to the fuel inlet pipe between the said first and second ends and also intended to be connected to the fuel tank is formed integrally with the fuel inlet pipe. The unit includes a tank for collecting fuel vapors disposed close to the first end of the fuel inlet pipe and formed integrally therewith.

Abstract: A gas-pressure relief valve unit, particularly for fuel vapours, comprising a body defining a chamber which communicates with first and second environments upstream and downstream of the unit respectively, through first and second apertures. The body is provided with a first and a second assemblies, the first assembly including a valve seat interposed between the apertures and an obturator urged by a resilient thrust element and movable between a position of engagement with the seat and a position spaced from it. The obturator can move away from the valve seat, overcoming the action of the resilient element, when a predetermined threshold value of the pressure differential between the environments is reached. When the obturator is engaged with the seat and the pressure differential between the environments is less than the predetermined threshold value, the valve means define a narrow passage which allows a small, continuous flow of gas between the first and second environments.