A damper device includes at least a diaphragm, an opposite member that faces the diaphragm and is connected to the diaphragm in a hermetically sealed state over a circumferential direction, and a deformation-suppressing member that is disposed in a hermetically sealed space defined by the diaphragm and the opposite member. The deformation-suppressing member includes a central portion that includes a concave surface of which a depth is increased toward a center in a radial direction thereof, and protruding portions that are provided closer to an outer peripheral side than the central portion.

A fuel system includes a low-pressure fuel delivery unit and a high-pressure fuel delivery unit which has a low-pressure region and a high-pressure region such that the low-pressure region supplies fuel to the high-pressure region which supplies the fuel to a plurality of high-pressure fuel injectors. A low-pressure fuel rail supplies fuel to low-pressure fuel injectors. A low-pressure fuel injector line is connected at a first end directly to the high-pressure fuel delivery unit and receives fuel from the low-pressure region and is connected at a second end directly to the low-pressure fuel rail, thereby providing fluid communication from the low-pressure region to the low-pressure fuel rail. A device is located between the low-pressure region and the low-pressure fuel rail and reduces fuel pressure pulsations.

A metal diaphragm damper includes disc-shaped damper main body having two diaphragms between which a gas is sealed and each of which is provided with a deformable portion at the center thereof and two regulation members that are disposed outside of the deformable portions of the two diaphragms. The metal diaphragm damper includes a first welding part provided with a first welding layer WD1 that seals an annular periphery portion of the regulation member and an outer edge portion of the diaphragm, and a second welding layer WD1 that seals an annular periphery portion of the other regulation member and an outer edge portion of the other diaphragm. The metal diaphragm damper further includes a second welding part provided with a welding layer WD2 that seals the annular periphery portions of the two regulation members.

A metal diaphragm damper which is resistant to breakage even if repeated stress is applied is provided. The metal diaphragm damper includes a diaphragm that is disk shaped and has a gas enclosed therein the diaphragm has a deforming action part in a center and an outer periphery fixing part on an outer periphery, the deforming action part is formed into a shape curved toward an exterior of the diaphragm, a folded part is formed in a connecting portion of the deforming action part and the outer periphery fixing part and is opened to an inner diameter side, and the folded part is movable in a radial direction.

A structure for attaching a metal diaphragm damper, includes a housing, a housing cover that cooperates with the housing to define a space, and a pair of diaphragms each formed in a disk shape, the pair of diaphragms having weld portions on an outer periphery side thereof, the weld portions being welded to each other in an annular shape to form the metal diaphragm damper of which inside is filled with gas, the metal diaphragm damper being attached to the housing and the housing cover so as to be disposed in the space between the housing and the housing cover. The pair of diaphragms is provided with outer peripheral portions on the outer peripheral side of the welded portions, and the outer peripheral portions of the pair of diaphragms are held by the housing and the housing cover in a thickness direction of the pair of diaphragms.

A damper device includes at least a diaphragm, an opposite member that faces the diaphragm and is connected to the diaphragm in a hermetically sealed state over a circumferential direction, and a deformation-suppressing member that is disposed in a hermetically sealed space defined by the diaphragm and the opposite member. The deformation-suppressing member includes a central portion that includes a concave surface of which a depth is increased toward a center in a radial direction thereof, and protruding portions that are provided closer to an outer peripheral side than the central portion.

The present disclosure relates to a pulsation dampening structure for a vehicle. The pulsation dampening structure includes a fuel rail, a rail plug disposed at an end portion of the fuel rail, and a pulsation dampening part disposed on the rail plug to dampen pulsation generated when fuel enters. A turbulent flow is caused by reflecting fuel which was entered, and a vortex is generated in the fuel, thereby dampening pulsation.

Provided is a high-pressure fuel supply pump capable of reducing a manufacturing cost of a part for holding a metal damper. The high-pressure fuel supply pump includes a pump body 1 having a pressurizing chamber 11 therein, a damper cover 14 forming a damper chamber 10 together with the pump body 1 on the upstream side of the pressurizing chamber 11, a metal damper 9 that is disposed in the damper cover 10 and formed by laminating two metal diaphragms, and a first holding member 9a that is disposed in the damper chamber 10 and presses and holds the metal damper 9 from one side. The first holding member 9a includes a first regulation portion that regulates the radial movement of the metal damper 9, and a second regulation portion that regulates the radial movement of the first holding member 9a in the damper chamber 10. At a position of the second regulation portion, a flow path is formed which allows the fuel in the damper chamber 10 to circulate to both surfaces of the metal damper 9.

In some examples, a fuel injector rail assembly may include a fuel rail including a tubular body, with a fuel outlet passage formed through a wall of the tubular body. An injector cup may be connected to the tubular body and may include an injector chamber configured to receive a fuel injector. A first fuel passage formed in the injector cup may include a first diameter, and the first fuel passage may be connected to the fuel outlet passage of the tubular body. Additionally, a second fuel passage may be formed in the injector cup between the first fuel passage and the injector chamber. The second fuel passage may have a second diameter that is smaller than the first diameter of the first fuel passage.

There is provided a damper unit that allows a plurality of damper bodies to be installed by simple work. The damper unit includes at least two damper bodies that are installed in a housing space so as to be stacked and include hermetically sealed spaces therein. The damper unit further an elastic member 7 that is disposed between the damper bodies, and a stopper that is installed across outer peripheral edge portions of the damper bodies positioned at both ends.