Bearing lubrication system for gear pump having clearance between bearing and housing wall for preventing entry of contaminants larger than lubrication passage

摘要

A gear pump suitable for pumping contaminated fuel has a lubrication passage in a pump bearing which receives fuel from the clearance volume between the bearing and the housing in the pump discharge arc. The clearance entrance between the bearing and the housing, which functions as a filter, is smaller than the passage so that contaminants traversing the clearance will not obstruct the passage. Since only contaminants smaller than the clearance entrance can enter the passage, the passage may be made sufficiently small so as not to adversely affect pump performance.