Prevention device of cavitation erosion damage in the fuel injection pump of the diesel engine

摘要

The present invention relates to an apparatus for preventing cavitation damage to a diesel engine fuel injection pump, wherein a pressure control valve for shutting a barrel port is mounted on a deflector or a barrel of the fuel injection pump to increase the fuel pressure in the barrel port during an early stage of fuel compression. This prevents fountain-type or jet-type cavitation from occurring before and after the opening of the barrel port during a late stage of fuel compression, thereby preventing corrosion damage caused by cavitation occurring mainly in a plunger and the barrel port of the fuel injection pump. The key technical features of the present invention are for an apparatus for preventing cavitation damage to a diesel engine fuel injection pump having a fuel intake valve and the barrel port for the inflow and outflow of fuel, respectively, comprising: a valve member mounted on the barrel port to shut the barrel port during an early stage of fuel compression performed by the upward movement of the plunger to increase the pressure in the barrel port; a valve housing installed in the deflector or the barrel of a pump housing to support the valve member; and a pressure control valve constituted by a spring interposed between the valve member and the valve housing to elastically support the valve member. The barrel port is shut to increase the pressure therein during the early stage of fuel compression, and thus preventing cavitation caused by the pressure difference between the barrel port and a pump chamber before and after the opening of the barrel port during the late stage of fuel compression. When the pressure of fuel in the barrel port exceeds a level higher than an open level, the barrel port opens to discharge fuel.