Abstract: A damper device is provided in a flow passage of a fluid. The damper device includes a plurality of diaphragm dampers that are stacked together. Each of the plurality of diaphragm dampers includes a first flexible portion, a second flexible portion, and a rim including a welded portion. A peripheral edge of the first flexible portion and a peripheral edge of the second flexible portion are welded together in the welded portion. Each of the plurality of diaphragm dampers is configured to seal a gas in an inner region between the first flexible portion and the second flexible portion. A coupler that couples the plurality of diaphragm dampers together includes holders that hold the rims of the plurality of diaphragm dampers. A gap is provided between the holder of the coupler and the welded portion of each of the plurality of diaphragm dampers.

Abstract: A pulsation damper includes an upper diaphragm, a lower diaphragm configured to form a sealed space having a predetermined pressure with the upper diaphragm, in which an inert gas is filled; and a deformation suppressing member formed of an elastic material, and comprising an inner cylindrical portion, and an extension portion extending from a center portion on an outer peripheral surface of the inner cylindrical portion such that the extension portion extends outward from a center axis of the inner cylindrical portion, wherein the deformation suppressing member is arranged inside the sealed space such that an outer periphery of the extension portion abuts against inner walls of the upper diaphragm and the lower diaphragm.

Abstract: A diaphragm includes a flange and a protrusion provided to protrude to one side of the flange, wherein the protrusion has at least two annular curved portions provided annularly on a ceiling portion having a flat surface-like shape and an outer side in a radial direction of the ceiling portion, in a state where pressure on an outer wall side of the protrusion and pressure on an inner wall side of the protrusion are the same, the at least two annular curved portions are each formed to be curved in a cross-section of the diaphragm obtained by cutting the diaphragm by a virtual plane including a center line of the diaphragm, the centers of curvature of the curved portions being arranged at different positions on a side opposite to a protruding direction of the protrusion, and the diaphragm is formed of a sheet metal.

Abstract: A pulsation damper includes an upper diaphragm, a lower diaphragm configured to form a sealed space having a predetermined pressure with the upper diaphragm, in which an inert gas is filled; and a deformation suppressing member formed of an elastic material, and comprising an inner cylindrical portion, and an extension portion extending from a center portion on an outer peripheral surface of the inner cylindrical portion such that the extension portion extends outward from a center axis of the inner cylindrical portion, wherein the deformation suppressing member is arranged inside the sealed space such that an outer periphery of the extension portion abuts against inner walls of the upper diaphragm and the lower diaphragm.

Abstract: A damper device is provided in a flow passage of a fluid. The damper device includes a plurality of diaphragm dampers that are stacked together. Each of the plurality of diaphragm dampers includes a first flexible portion, a second flexible portion, and a rim including a welded portion. A peripheral edge of the first flexible portion and a peripheral edge of the second flexible portion are welded together in the welded portion. Each of the plurality of diaphragm dampers is configured to seal a gas in an inner region between the first flexible portion and the second flexible portion. A coupler that couples the plurality of diaphragm dampers together includes holders that hold the rims of the plurality of diaphragm dampers. A gap is provided between the holder of the coupler and the welded portion of each of the plurality of diaphragm dampers.

Abstract: A cylinder is configured into a bottomed tubular form and includes an inner peripheral wall, an inner bottom wall, an outer peripheral wall and an intake hole and a discharge hole. The inner peripheral wall slidably guides the plunger. The intake hole and the discharge hole communicate between the inner peripheral wall and the outer peripheral wall. A pump housing includes a cylinder receiving hole that includes an inner peripheral wall, into which the cylinder is inserted. A pressurizing chamber is formed by the inner peripheral wall and the inner bottom wall of the cylinder and a distal end outer wall of the plunger.

Abstract: A diaphragm includes a flange and a protrusion provided to protrude to one side of the flange, wherein the protrusion has at least two annular curved portions provided annularly on a ceiling portion having a flat surface-like shape and an outer side in a radial direction of the ceiling portion, in a state where pressure on an outer wall side of the protrusion and pressure on an inner wall side of the protrusion are the same, the at least two annular curved portions are each formed to be curved in a cross-section of the diaphragm obtained by cutting the diaphragm by a virtual plane including a center line of the diaphragm, the centers of curvature of the curved portions being arranged at different positions on a side opposite to a protruding direction of the protrusion, and the diaphragm is formed of a sheet metal.

Abstract: A valve seat member, which partitions between a supply passage and a pressurizing chamber, includes an inner flow path, which communicates between the supply passage and the pressurizing chamber, and an outer flow path, which is placed on a radially outer side of the inner flow path. An inner valve is seatable against an inner valve seat formed in an opening of the inner flow path. An outer valve is contactable with an end surface of the inner valve, which is opposite from the inner valve seat. The outer valve is seatable against an outer valve seat, which is formed in an opening of the outer flow path.

Abstract: A valve seat member which partitions between a supply passage and a pressurizing chamber, includes an inner flow path, which communicates between the supply passage and the pressurizing chamber, and an outer flow path, which is placed on a radially outer side of the inner flow path. An inner valve is seatable against inner valve seat formed in an opening of the inner flow path. An outer valve is contactable with an end surface of the inner valve, which is opposite from the inner valve seat. The outer valve is seatable against an outer valve seat, which is formed in an opening of the outer flow path.

Abstract: A valve seat member, which partitions between a supply passage and a pressurizing chamber, includes an inner flow path, which communicates between the supply passage and the pressurizing chamber, and an outer flow path, which is placed on a radially outer side of the inner flow path. An inner valve is seatable against an inner valve seat formed in an opening of the inner flow path. An outer valve is contactable with an end surface of the inner valve, which is opposite from the inner valve seat. The outer valve is seatable against an outer valve seat, which is formed in an opening of the outer flow path.

Abstract: A cylinder is configured into a bottomed tubular form and includes an inner peripheral wall, an inner bottom wall, an outer peripheral wall and an intake hole and a discharge hole. The inner peripheral wall slidably guides the plunger. The intake hole and the discharge hole communicate between the inner peripheral wall and the outer peripheral wall. A pump housing includes a cylinder receiving hole that includes an inner peripheral wall, into which the cylinder is inserted. A pressurizing chamber is formed by the inner peripheral wall and the inner bottom wall of the cylinder and a distal end outer wall of the plunger.

Abstract: A plunger stopper is installed to a cylinder hole forming portion of a cylinder forming member. The plunger stopper cooperates with a step portion of a plunger to limit movement of the plunger in a state where a slide surface of the plunger contacts an inner peripheral wall surface of the cylinder hole.

Abstract: A cylinder is configured into a bottomed tubular form and includes an inner peripheral wall, an inner bottom wall, an outer peripheral wall and an intake hole and a discharge hole. The inner peripheral wall slidably guides the plunger. The intake hole and the discharge hole communicate between the inner peripheral wall and the outer peripheral wall. A pump housing includes a cylinder receiving hole that includes an inner peripheral wall, into which the cylinder is inserted. A pressurizing chamber is formed by the inner peripheral wall and the inner bottom wall of the cylinder and a distal end outer wall of the plunger.

Abstract: A cylinder is configured into a bottomed tubular form and includes an inner peripheral wall, an inner bottom wall, an outer peripheral wall and an intake hole and a discharge hole. The inner peripheral wall slidably guides the plunger. The intake hole and the discharge hole communicate between the inner peripheral wall and the outer peripheral wall. A pump housing includes a cylinder receiving hole that includes an inner peripheral wall, into which the cylinder is inserted. A pressurizing chamber is formed by the inner peripheral wall and the inner bottom wall of the cylinder and a distal end outer wall of the plunger.

Abstract: A pulsation dumper configured to reduce a fuel pressure pulsation of fuel flowing in a fuel chamber includes a sealed space in which gas having a predetermined pressure is encapsulated between a first diaphragm and a second diaphragm configured to be resiliently deformable by a fuel pressure pulsation in the fuel chamber. A first resilient member provided in the sealed space abuts against an inner wall of the first diaphragm, and a second resilient member abuts against an inner wall of a second diaphragm. A supporting member provided between the first resilient member and the second resilient member supports an outer peripheral portion of the first resilient member and an outer peripheral portion of the second resilient member. A resonance of first and second diaphragms is restrained by the first and second resilient members. The first and second resilient members do not impair deformation of center portions of the first and second diaphragms.

Abstract: A valve seat member which partitions between a supply passage and a pressurizing chamber, includes an inner flow path, which communicates between the supply passage and the pressurizing chamber, and an outer flow path, which is placed on a radially outer side of the inner flow path. An inner valve is seatable against inner valve seat formed in an opening of the inner flow path. An outer valve is contactable with an end surface of the inner valve, which is opposite from the inner valve seat. The outer valve is seatable against an outer valve seat, which is formed in an opening of the outer flow path.

Abstract: At least one choked flow passage communicates between one side of the movable member and the other side of the movable member and limits an amount of fuel, which passes from the one side of the movable member to the other side of the movable member, when the movable member is moved by an urging force of a relief spring toward a valve element. A larger amount of fuel, which is larger than the amount of fuel that is passable through the at least one choked flow passage, flows from a first return flow passage to a second return flow passage, when the movable member is moved toward the other side, which is opposite from the valve element, against the urging force of the relief spring.

Abstract: A gas chamber is placed adjacent to a variable volume chamber of a high pressure pump. The gas chamber includes an inner blocking wall, which borders on the variable volume chamber and contacts fuel in the variable volume chamber, an outer blocking wall, which is opposed to the inner blocking wall, and gas, which fills a space that is defined between the inner blocking wall and the outer blocking wall.

Abstract: A plunger stopper is installed to a cylinder hole forming portion of a cylinder forming member. The plunger stopper cooperates with a step portion of a plunger to limit movement of the plunger in a state where a slide surface of the plunger contacts an inner peripheral wall surface of the cylinder hole.

Abstract: A cylinder is configured into a bottomed tubular form and includes an inner peripheral wall, an inner bottom wall, an outer peripheral wall and an intake hole and a discharge hole. The inner peripheral wall slidably guides the plunger. The intake hole and the discharge hole communicate between the inner peripheral wall and the outer peripheral wall. A pump housing includes a cylinder receiving hole that includes an inner peripheral wall, into which the cylinder is inserted. A pressurizing chamber is formed by the inner peripheral wall and the inner bottom wall of the cylinder and a distal end outer wall of the plunger.