Patent ID: 8382458

Claim:
A high-pressure fuel pump comprising: a plunger which slidably fits to a cylinder and reciprocates for pressurizing and discharging a fuel taken in a pressurizing chamber; an inlet valve device for taking in a fuel into the pressurizing chamber; an outlet valve device for discharging the pressurized fuel from the pressurizing chamber; and a communicating pass which comprises a hole or a groove formed in the cylinder, and communicates between a pressurized fuel area in the pressurizing chamber and a gap between the cylinder and the plunger; wherein the high-pressure fuel pump is configured so that a head side portion of the cylinder protrudes into the pressurizing chamber, and thereby an outer surface of the head side portion of the cylinder is located so as to contact with the pressurized fuel in the pressurizing chamber; and wherein one end of the communicating pass opens at the pressurized fuel area on an outer surface of the cylinder and the other end of the communicating pass opens on an inner surface of the cylinder where the plunger slidably reciprocates.