Patent attributes
A fuel pump includes: an outer gear; an inner gear that is meshed with the outer gear and includes a receiving hole; a rotatable shaft; a contact portion that is formed to be contactable with the receiving hole; and a pump housing that rotatably receives the outer gear and the inner gear and includes a first housing component and a second housing component, between which the inner gear is held in the axial direction. At least one of the receiving hole and the contact portion includes a tilt surface, which is tilted relative to the axis direction. When the rotatable shaft is rotated to a drive rotation side, the receiving hole contacts the contact portion through the tilt surface, so that the receiving hole is urged in a circumferential direction and is also urged toward the first housing component in the axial direction.