Abstract: A small-diameter circular column portion having a diameter slightly smaller than that of a small-diameter hole (press-fitting hole) of an inside-outside communication hole is formed at a press-fitting end portion of a bush. A narrow annular clearance is formed between the small-diameter circular column portion and the small-diameter hole when the bush is press-fitted. Even if a press-fitting burr is produced at the press-fitting end portion during manufacturing of a common rail, the press-fitting burr is confined in the depth of the annular clearance. Even when fuel flows through the inside-outside communication hole during engine operation, movement of the fuel and the fuel flow acting on the press-fitting burr are limited in the depth of the annular clearance, inhibiting the press-fitting burr from dropping out or flowing out. Thus, a highly reliable common rail can be provided at low cost.

Abstract: A small-diameter circular column portion having a diameter slightly smaller than that of a small-diameter hole (press-fitting hole) of an inside-outside communication hole is formed at a press-fitting end portion of a bush. A narrow annular clearance is formed between the small-diameter circular column portion and the small-diameter hole when the bush is press-fitted. Even if a press-fitting burr is produced at the press-fitting end portion during manufacturing of a common rail, the press-fitting burr is confined in the depth of the annular clearance. Even when fuel flows through the inside-outside communication hole during engine operation, movement of the fuel and the fuel flow acting on the press-fitting burr are limited in the depth of the annular clearance, inhibiting the press-fitting burr from dropping out or flowing out. Thus, a highly reliable common rail can be provided at low cost.

Abstract: A flow damper is provided with a clearance to absorb a deformation occurring in proximate to a lower end of the valve body by the clearance on an entire outer circumference of a lower side of a large diameter portion of a piston. By the configuration in this manner, even if the slight deviation in the accuracy or the shape of the seat surface occurs a radially inward deformation of a lower portion of the valve body when the valve body is fastened to the common rail body at a large axial force, the clearance absorbs the deformation. Thus, the deformation of the valve body does not affect the piston sliding hole. Accordingly, a sliding clearance of the piston does not change, not to spoil a slide motion of the piston.

Abstract: A flow damper is provided with a clearance to absorb a deformation occurring in proximate to a lower end of the valve body by the clearance on an entire outer circumference of a lower side of a large diameter portion of a piston. By the configuration in this manner, even if the slight deviation in the accuracy or the shape of the seat surface occurs a radially inward deformation of a lower portion of the valve body when the valve body is fastened to the common rail body at a large axial force, the clearance absorbs the deformation. Thus, the deformation of the valve body does not affect the piston sliding hole. Accordingly, a sliding clearance of the piston does not change, not to spoil a slide motion of the piston.