Patent ID: 8342423

Claim:
A fuel injection apparatus ( 1 ) for an internal combustion engine comprising: a fuel supply passage ( 16 ); a valve arrangement for controlling fuel pressure within the fuel supply passage ( 16 ), the valve arrangement including a valve member ( 46 ) movable between an open position in which the fuel supply passage ( 16 ) communicates with a low pressure fuel drain and a closed position in which communication between the fuel supply passage ( 16 ) and the low pressure fuel drain is prevented; and damping means ( 51 , 52 ) for controlling and/or damping movement of the valve member between the closed and open positions, wherein the valve member ( 46 ) is movable within a bore ( 45 ) disposed in a housing ( 41 ), the bore ( 45 ) defined about a longitudinal axis, the bore ( 45 ) being closed at one end thereof, wherein the damping means comprises a damping chamber ( 52 ) defined between the closed end ( 53 ) of the bore ( 45 ) and the valve member ( 46 ), the damping chamber ( 52 ) having an exit or outlet ( 51 ) for controlling the rate of fuel flow into and/or out of the damping chamber ( 52 ), thereby to provide a damping effect on the valve member ( 46 ); characterized in that one of the circumferential surface of the bore or the surface of the valve member that faces the circumferential surface of the bore ( 45 ) defines a collection means ( 60 , 62 ), said collection means axially located between the fuel supply passage ( 16 ) and the damping chamber ( 52 ) for hindering or substantially preventing fuel leakage between the valve member ( 46 ) and the bore ( 45 ) from entering into the damping chamber ( 52 ), the collection means comprising a volume ( 60 ) for collecting fuel leaking between the valve member ( 46 ) and the bore ( 45 ), wherein the volume ( 60 ) is in continuous fluid communication with the low pressure fuel drain both when the valve member ( 46 ) is in the open position and when the valve member ( 46 ) is in the closed position.