Abstract: A mechanism for reducing pressure pulsation includes a pair of metal dampers formed by joining two disk-shaped metal diaphragms over an entire circumference and forming a hermetically sealed space inside a joined portion, with gas being sealed in the aforementioned hermetically sealed space of the damper, has a pair of pressing members which give pressing forces to both outer surfaces of the aforementioned metal dampers at a position at an inner diameter side from the joined portion, and is unitized with the pair of pressing members being connected in a state in which they sandwich the metal damper.

Abstract: To obtain a small and high performance damper mechanism which reduces pressure pulsation in low pressure-side fuel in the high pressure fuel pump in a high pressure fuel supply system or a high pressure fuel pump provided with the small and high performance damper mechanism. Two metal diaphragms are welded together over the entire circumference to obtain a metal diaphragm assembly (also referred to as “double metal diaphragm damper”). The whole or part of the portion of the metal diaphragm assembly other than the weld (for example, the portion inside the weld) is clamped by a pressing member and thereby the assembly is secured in a housing enclosure. The housing enclosure may be formed integrally with the body of a high pressure pump.

Abstract: A high-pressure fuel supply pump having a fuel relief path for connecting a high-pressure fuel path downstream of a discharge valve for discharging fuel pressurized in a pressurizing chamber to a low-pressure fuel path upstream of an inlet valve or the pressurizing chamber, a check valve being provided in the fuel relief path as a relief valve for allowing the fuel to flow only to the low-pressure fuel path or the pressurizing chamber, wherein an energy attenuating mechanism is provided in a discharge path on a side facing the discharge valve upstream of the relief valve in the fuel relief path so as to prevent an instantaneous pressure rise caused in the discharge path from propagating to the relief valve.

Abstract: A high-pressure fuel pump is comprises of: a plunger which slidably fits to a cylinder and reciprocates for pressurizing and discharging a fuel taken in a pressurizing chamber; an inlet valve device for taking in a fuel into the pressurizing chamber; an outlet valve device for discharging the pressurized fuel from the pressurizing chamber; and a communicating pass which comprises a hole or a groove formed in the cylinder, and communicates between a pressurized fuel area and a gap between the cylinder and the plunger.

Abstract: To obtain a small and high performance damper mechanism which reduces pressure pulsation in low pressure-side fuel in the high pressure fuel pump in a high pressure fuel supply system or a high pressure fuel pump provided with the small and high performance damper mechanism. Two metal diaphragms are welded together over the entire circumference to obtain a metal diaphragm assembly (also referred to as “double metal diaphragm damper”). The whole or part of the portion of the metal diaphragm assembly other than the weld (for example, the portion inside the weld) is clamped by a pressing member and thereby the assembly is secured in a housing enclosure. The housing enclosure may be formed integrally with the body of a high pressure pump.

Abstract: To obtain a small and high performance damper mechanism which reduces pressure pulsation in low pressure-side fuel in the high pressure fuel pump in a high pressure fuel supply system or a high pressure fuel pump provided with the small and high performance damper mechanism. Two metal diaphragms are welded together over the entire circumference to obtain a metal diaphragm assembly (also referred to as “double metal diaphragm damper”). The whole or part of the portion of the metal diaphragm assembly other than the weld (for example, the portion inside the weld) is clamped by a pressing member and thereby the assembly is secured in a housing enclosure. The housing enclosure may be formed integrally with the body of a high pressure pump.

Abstract: To obtain a small and high performance damper mechanism which reduces pressure pulsation in low pressure-side fuel in the high pressure fuel pump in a high pressure fuel supply system or a high pressure fuel pump provided with the small and high performance damper mechanism. Two metal diaphragms are welded together over the entire circumference to obtain a metal diaphragm assembly (also referred to as “double metal diaphragm damper”). The whole or part of the portion of the metal diaphragm assembly other than the weld (for example, the portion inside the weld) is clamped by a pressing member and thereby the assembly is secured in a housing enclosure. The housing enclosure may be formed integrally with the body of a high pressure pump.

Abstract: A seal mechanism with improved pressure tightness is provided to eliminate a return piping to a fuel tank used for reducing pressure applied to the seal mechanism in a high pressure fuel pump. The seal mechanism includes a stress reduction mechanism for reducing the stress generated at the junction between its retaining member and flexible member.

Abstract: A seal mechanism with improved pressure tightness is provided to eliminate a return piping to a fuel tank used for reducing pressure applied to the seal mechanism in a high pressure fuel pump. The seal mechanism includes a stress reduction mechanism for reducing the stress generated at the junction between its retaining member and flexible member.

Abstract: An axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump includes a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

Abstract: The present invention provides an axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump comprises a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

Abstract: The present invention provides an axial plunger pump which does not need bellows by restricting fuel to a cylinder bore configuring a pump portion and by lubricating the other portion with oil. The high pressure fuel pump comprises a plunger reciprocating according to a shaking movement of a swash plate, a cylinder block forming a pump chamber together with the plunger, and a sealing member provided between the plunger and a cylinder bore for sealing oil leaked from the pump chamber to a chamber surrounding the pump chamber, wherein oil in the oil chamber is supplied from the outside of the high pressure fuel pump.

Abstract: An axial plunger pump according to the present invention is constructed so as to comprise a shaft having a swash plate effecting swing motion and transmitting driving force from the outside, plungers each reciprocating by the swing motion of the swash plate, a cylinder block having cylinders formed so as to open on the side of the swash plate and inserting therein the plungers and having passages for supplying fuel to the cylinders, a body combined with the cylinder block to enclose the swash plate, and sealing members arranged between the plungers and the cylinders on the swash plate side of the passages formed in the cylinder block for sealing gaps between the plungers and the cylinders, respectively.

Abstract: An axial plunger pump includes a shaft having a swash plate effecting swing motion and transmitting driving force from the outside, plungers reciprocate by the swing motion of the swash plate. A cylinder block has cylinders formed so as to open on the side of the swash plate, with the plungers inserted therein. Passages in the block supply refuel to the cylinders. A body combined with the cylinder block encloses the swash plate. Sealing members are arranged between the plungers and the cylinders on the swash plate side of the passages formed in the cylinder block for sealing gaps between the plungers and the cylinders, respectively.