High-pressure fuel supply pump

A high-pressure fuel supply pump system comprising:

• a pump body configured to form a pressurizing chamber at an inner wall portion;
• and
• a flange portion configured to fix the pump body to a mounting portion for a high-pressure fuel supply pump within an internal combustion engine;
• wherein the pump body is provided with a first hole having a first cross sectional area forming the pressurizing chamber, a second hole communicating with the first hole, being formed on the side opposite to the pressurizing chamber, and having a second cross sectional area larger than the first cross sectional area, and a third hole communicating with the second hole, being formed on the side opposite to the pressurizing chamber, and having a third cross sectional area larger than the second cross sectional;
• and
• wherein the high-pressure fuel supply pump comprises:
• a cylinder which is inserted from an opposite side of the pressurizing chamber toward the pressurizing chamber and whose uppermost end surface is in contact with an upper end surface of a portion forming the second hole of the pump body;
• a plunger disposed to slide on an inner diameter side of the cylinder;
• and
• a spring holding member which has a holding portion holding a spring portion for biasing the plunger and is inserted from the opposite side of the pressurizing chamber toward the pressurizing chamber and is configured to face a portion forming the third hole of the pump body;
• wherein a spring contact portion of the spring holding member is disposed above a lowermost end portion of the flange portion;
• and
• wherein the spring portion is configured to contact the spring contact portion.

A high-pressure fuel supply pump system comprising:

• a pump body configured to form a pressurizing chamber at an inner wall portion;
• and
• a flange portion configured to fix the pump body to a mounting portion for a high-pressure fuel supply pump within an internal combustion engine;
• wherein the high-pressure fuel supply pump comprises:
• an insertion portion inserted into the mounting portion;
• a plunger disposed to slide on an inner diameter side of a cylinder;
• and
• a spring holding member having an outer peripheral portion fixed to the insertion portion and a holding portion holding a spring portion for biasing the plunger on the radially inner side of the outer peripheral portion;
• wherein when the high-pressure fuel supply pump is attached to the mounting portion, in a state where the spring portion is contracted, half or more of the entire length of the spring portion is positioned closer to the pressurizing chamber side than a lower end portion of the insertion portion or a lower end portion of the outer peripheral portion of the spring holding member;
• wherein a spring contact portion of the spring holding member that is a lowermost end portion of the spring holding member is disposed above a lowermost end portion of the flange portion;
• and
• wherein the spring contact portion is configured to contact the spring-side lowermost end portion.