High pressure fuel pump with parallel cooling fuel flow

摘要

A high pressure fuel pump with parallel cooling fuel flow is disclosed wherein a fuel pump barrel having a substantially cylindrical plunger bore with an annular drain groove is provided. A first fuel path is provided that fluidically couples a fuel supply to an annular cooling ring formed on the outer surface of the barrel. The first fuel path further fluidically couples the annular cooling ring to a storage tank via an exit passage. A second, parallel fuel path is provided that fluidically couples the first fuel path to the drain groove, and further includes a drain passage fluidically coupled to the drain groove and the first fuel path via the storage tank.