High pressure pump

A high pressure pump configured to be installed to an internal combustion engine to pressurize, discharge and supply fuel to the internal combustion engine, the high pressure pump comprising:

• a housing that includes a pressurizing chamber;
• a plunger that is movable in such a manner that the plunger increases and decreases a volume of the pressurizing chamber upon movement of the plunger, and thereby the plunger is operable to pressurize the fuel in the pressurizing chamber;
• a fuel chamber forming portion that is placed on a radially outer side of the plunger and forms a fuel chamber that is communicated with the pressurizing chamber, wherein the fuel chamber forming portion includes a casing, which forms the fuel chamber at an inside of the casing while the casing is formed separately from the housing and is installed to an outer peripheral wall of the housing, and the fuel chamber is defined between one wall portion and another wall portion of the casing in a radial direction of an axis of the plunger;
• a pulsation damper that is placed in an inside of the fuel chamber of the casing and is operable to reduce pressure pulsation of the fuel in the fuel chamber, wherein the pulsation damper is held between the one wall portion and the another wall portion of the casing in the radial direction;
• a discharge portion that discharges the fuel, which is pressurized in the pressurizing chamber;
• and
• a fixable portion that is placed on the radially outer side of the plunger and includes a receiving through-hole while the fixable portion is configured to be fixed to the internal combustion engine with a fixing member that is formed to correspond with the receiving through-hole, wherein:
• the casing is placed at a location that is displaced from an axis of the receiving through-hole;
• a portion of the casing, an entirety of the fixable portion and an entirety of the discharge portion are placed on an inner side of an imaginary cylindrical surface that circumferentially extends about the axis of the plunger along an end part of the discharge portion;
• another portion of the casing is placed on an outer side of the imaginary cylindrical surface;
• and
• the fixable portion is configured to be directly fixed to an engine head of the internal combustion engine with the fixing member.