Mechanism for restraining fuel pressure pulsation and high pressure fuel supply pump of internal combustion engine with such mechanism

A high-pressure fuel supply pump comprising:

• a pump body including a pressure chamber, a partition member mounted on the pump body and including a damper chamber, disposed between a housing of the pump body and a damper cover of the pump body, a low-pressure fuel path for supplying therethrough the pressure chamber, and a damper mechanism for reducing fuel pressure pulsation contained in the damper chamber, the pressure pulsation reducing damper mechanism having a metal damper including a pair of disk-shaped metal diaphragms joined with each other at their peripheries to form therein a sealed chamber filled with gas, and
• a pair of pressing members between which the metal damper is clamped at its radially inner side with respect to the peripheries to apply a pressing force to each of outer surfaces of the metal damper, said pressing members and said pair of disk-shaped metal diaphragms together forming a unitized damper unit receivable in the damper chamber.