CONNECTION DESIGN FOR A BRANCH TUBE IN A HIGH PRESSURE FUEL RAIL

摘要

In causing a pressure head portion on the terminal of a branch pipe to be abutted and tightly pressed against a pressure receiving bearing surface formed in a through hole in a high-pressure fuel rail, the pressure bearing surface is formed in the shape of a spherical surface having a curvature radius ( gamma ) of 0.4D to 10D, wherein D is the diameter of the branch pipe. Since the branch pipe has such a spherical pressure bearing surface, a uniform surface pressure can be obtained should the branch pipe be installed in an inclined state, and such an inclination or eccentricity can be rectified by the shapes of the pressure receiving bearing surface and the pressure bearing surface to provide a uniform surface pressure.