Patent ID: 9057348
Filing Date: 2015-06-16
Classification: F02M,F04B

Abstract:
1. A pulsation damper provided for a fuel chamber of a high-pressure fuel pump, the pulsation damper comprising: a diaphragm having a displacement section that is displaced by pressure acting there against, the diaphragm reducing pressure pulsation in the fuel chamber by means of displacement of the displacement section; and a pump cover of the high-pressure fuel pump for supporting the diaphragm, the pump cover, together with the diaphragm, forms a gas chamber, wherein the displacement section includes an annular projection and a flat section that has a flat surface facing the gas chamber and a flat surface facing the fuel chamber, the annular projection surrounding the flat section, the pump cover includes an annular projection and a flat section that has a flat surface facing the gas chamber, the flat surface parallel to the flat surface of the displacement section that faces the gas chamber, the annular projection of the pump cover surrounding the flat section of the pump cover, the diaphragm is shaped like a lidded cylinder and has a bottom, which is formed by the displacement section, and a cylindrical circumferential section, which extends perpendicularly from the displacement section and continues to an outer periphery of the annular projection, the annular projection of the displacement section has an arcuate cross-sectional shape to bulge into the fuel chamber with respect to the flat section of the displacement section, the cylindrical circumferential section is perpendicular to the flat section of the displacement section, extends in a direction opposite to the bulging direction of the annular projection of the displacement section, and an inner circumferential surface of the cylindrical circumferential section has a fitting section that is joined to an outer circumferential surface of the annular projection of the pump cover while being fitted about the outer circumferential surface of the annular projection of the pump cover, and a whole outer circumferential surface of the cylindrical circumferential section faces and is exposed to the fuel chamber.