A high-pressure pump includes a pressurizing chamber forming portion, a suction passage forming portion, a seat member, a valve member, a cylindrical member, a needle, a movable core, a biasing member, a fixed core, and a coil including a winding portion. The coil generates an attractive force between the fixed core and the movable core when the winding portion is energized. The coil includes an outer cylindrical surface and multiple inner cylindrical surfaces that have different diameters. The multiple inner cylindrical surfaces are arranged in order of increasing diameter in a direction toward a pressurizing chamber. The movable core has an end surface that faces the fixed core, and the end surface of the movable core is located between a center, in an axial direction, of a smallest diameter one of the plurality of inner cylindrical surfaces and a center, in an axial direction, of the outer cylindrical surface.

A fuel injection system includes a fuel rail, and a damper that is disposed inside the fuel rail. The damper includes outwardly protruding first barbs formed integrally on one end of the damper and outwardly protruding second barbs formed integrally on an opposed end of the damper. The first barbs and the second barbs each engage the fuel rail inner surface, whereby the damper is located and retained within the fuel rail. The first barbs and the second barbs may be generally triangular in profile and each extend at an acute angle relative to the damper longitudinal axis. In addition, the first barbs and the second barbs are each oriented in the same direction relative to the longitudinal direction, whereby the damper is asymmetric when viewed in side view.

An object of the present invention is to obtain a high pressure fuel supply pump capable of reducing pressure pulsation that occurs in a low pressure pipe, preventing damage to the low pressure pipe, or reducing noise due to vibrations of the low pressure pipe. The present invention provides a high pressure fuel supply pump of a type in which, from a fuel suction port connected to a low pressure pipe provided upstream of a fuel, a low pressure passage, an electromagnetic suction valve driven by an electromagnetic force, a pressurizing chamber in which the volume thereof is increased or reduced by a plunger that is reciprocatingly moved by being guided by a cylinder, and a discharge valve provided at an outlet of the pressurizing chamber are sequentially arranged, a fuel is sucked to the pressurizing chamber through the electromagnetic suction valve, the amount of a part of the fuel, which is sucked to the pressurizing chamber, to be returned to the low pressure passage side is adjusted so that the amount of the fuel to be discharged through the discharge valve is controlled, and the high pressure fuel supply pump includes a backflow suppression mechanism for suppressing backflow of fuel from the fuel from the fuel suction portion to the low pressure pipe side.

Peripheral sections of two diaphragms are stacked on each other. The peripheral sections of the two diaphragms form an outer rim of a diaphragm damper. The outer rim is continuously sealed and joined by laser welding over the entire circumference of the outer rim. The thickness of the tip of the outer rim is set in correspondence with the spot diameter of a laser beam at the tip of the outer rim. A weld bead is formed by welding in the entire area of the tip of the outer rim.

A fuel system for an internal combustion engine includes an outlet conduit having an internal volume and also having an exterior surface that is exposed to an environment. The fuel system also includes a pressure pulsation damper which includes a pressure pulsation damper wall made of a resilient and compliant polymer material which defines a pressure pulsation damper chamber. The pressure pulsation damper wall extends along, and is centered about, a pressure pulsation damper axis such that the pressure pulsation damper wall circumferentially surrounds the pressure pulsation damper axis, thereby defining the pressure pulsation damper chamber which is circumferentially surrounded by the pressure pulsation damper wall, the pressure pulsation damper wall having an inner wall surface which is in fluid communication with the internal volume of the outlet conduit and also having an outer wall surface which is exposed to the environment.

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.

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.

The invention relates to a fuel injection device (100) for a compression-ignition engine, comprising a first storage unit (20) which can be supplied with fuel by at least one high-pressure pump (16), the first storage unit (20) being arranged preferably inside the high-pressure pump (16), a first connecting line (26) from the first storage unit (20) to a second storage unit (30), and a second connecting line (40) from the second storage unit (30) to a fuel injector (50).

A device for dampening pulsations of a fluid includes a case which includes an upper portion and a lower portion and a diaphragm elastically deformable between a rest position and a stressed position, arranged inside the case so that the diaphragm delimits, together with the lower portion, a fluid-tight chamber. More particularly, the diaphragm has, in the rest position, a general shape of revolution around a main axis of the device cambered towards the outside of the chamber. Furthermore, the profile of the diaphragm has according to an axial section of the diaphragm at least one undulation projecting towards the inside of the chamber in the rest position so as to form an area of preferred deformation towards the inside of the chamber in the stressed position of the diaphragm.

A fuel pressure regulator includes a housing having a housing bore and a housing inlet; a piston located within the housing bore such that the piston and the housing bore define an accumulation chamber and such that the piston moves between a first piston position where the accumulation chamber is minimized in volume and a second piston position where the accumulation chamber is maximized in volume, the piston having a piston bore with a piston inlet and a piston outlet and a valve seat defined therebetween; a piston spring which biases the piston toward the first piston position; a valve closure which moves between a seated position which prevents fluid communication from the piston inlet to the piston outlet and an unseated position which provides fluid communication from the piston inlet to the piston outlet; and a valve closure spring which biases the valve closure toward the seated position.