Patent ID: 8839764

Claim:
A fuel supply system for heavy oil common-rail injection systems for internal combustion engines, including a tank ( 1 ), a primary feed pump ( 3 ) for delivering heavy oil from the tank ( 1 ) to a high-pressure pump ( 5 ), wherein the high-pressure pump ( 5 ), via at least one high-pressure line ( 12 ), is connected to a high-pressure accumulator (rail) ( 6 ) feeding at least one injector ( 8 ), and, furthermore, a purge valve ( 9 ), which is connected to the high-pressure accumulator via a separate high-pressure line ( 15 ) for directing at least a portion of the heavy oil back into the tank ( 1 ) via a return line, wherein the purge valve ( 9 ) comprises a valve member ( 28 ) which is movable between an opened and a closed position, a high-pressure connection for a high-pressure line ( 15 ) communicating with a heavy oil high-pressure accumulator (rail) ( 6 ), a low-pressure connection for a return line, and actuating means for actuating the valve member ( 28 ), characterized in that the valve seat ( 29 ) of the valve member ( 28 ) is designed as a sliding seat.