US Patent 10429071 Fuel injector

A staged fuel injector comprises a pilot inner air swirler arranged along a centre axis of the injector, a pilot fuel swirler arranged radially outboard of the pilot inner air swirler, a main inner air swirler arranged radially outboard of the pilot fuel swirler and a main fuel swirler arranged radially outboard of the pilot fuel swirler. A fuel feed arm is arranged in fluid communication with the pilot fuel swirler and the main fuel swirler for delivering fuel to the pilot fuel swirler and the main fuel swirler and a heat protective casing enclosing the fuel feed arm, the pilot fuel swirler and the main fuel swirler.