Patent ID: 6932284

Claim:
An electromagnetic fuel injector ( 1 ) for an internal combustion engine; the injector ( 1 ) comprising a main body ( 4 ) having a central cylindrical cavity ( 5 ) adapted to act as a duct for the fuel, a valve ( 6 ) which is disposed to close an end of the central cylindrical cavity ( 5 ) in order to regulate the flow of fuel and is provided with a moving shutter ( 9 ), and an electromagnetic actuator ( 13 ) which is provided with a coil ( 15 ) disposed coaxially about the central cylindrical cavity ( 5 ), a fixed armature ( 17 ) of ferromagnetic material, and a moving armature ( 18 ) of ferromagnetic material mechanically connected to the shutter ( 9 ) and adapted to be magnetically attracted by the fixed armature ( 17 ) against the action of a spring ( 19 ); the injector ( 1 ) further comprising a monolithic tubular member ( 24 ) which is made from ferromagnetic material, is disposed coaxially within the central cylindrical cavity ( 5 ) of the main body ( 4 ) and houses the fixed armature ( 17 ) and the moving armature ( 18 ) of the electromagnetic actuator ( 13 ); the injector ( 1 ) being characterised in that the fixed armature ( 17 ) and the moving armature ( 18 ) are made from a first ferromagnetic material, while the tubular member ( 24 ) is made from a second ferromagnetic material having a lower magnetic permeability than the first ferromagnetic material.