High pressure pump

A high pressure pump comprising:

• a pressurization portion including a pressurization room whose volume is varied by a motion of a plunger to be capable of pressurizing a fuel;
• a discharge portion discharging the fuel pressurized in the pressurization room to a fuel rail;
• a body portion including:
• a relief passage through which the fuel flows from a downstream passage located downstream of the discharge portion to an upstream passage located upstream of the discharge portion;
• an inlet through which the relief passage and the downstream passage communicate with each other;
• a valve seat that is provided on a radially outer side of the inlet and has an annular shape;
• and
• an outlet through which the relief passage and the upstream passage communicate with each other,
• a valve member including a large diameter portion and a small diameter portion, the small diameter portion being located between the valve seat and the large diameter portion and having an outer diameter smaller than an outer diameter of the large diameter portion, the small diameter portion contacting the valve seat so as to close the inlet of the body portion when a pressure in the downstream passage is below a predetermined pressure, the valve member moving apart from the valve seat in a separation direction so as to open the inlet of the body portion when the pressure in the downstream passage is at or above the predetermined pressure;
• an urging member urging the valve member toward the valve seat;
• a valve hold member surrounding and holding the large diameter portion;
• and
• a limiting portion capable of limiting a motion of the valve hold member in the separation direction, wherein:
• the valve member includes an engagement surface located apart in the separation direction from the valve seat, the engagement surface being capable of contacting an edge portion of the valve hold member;
• the valve hold member is capable of decreasing in size in a radial direction and holding the small diameter portion;
• and
• when the valve hold member holds the small diameter portion, the valve hold member contacts the engagement surface.