A high pressure pump includes a housing with a chamber formed inside and a flow control valve and a discharge check valve installed in the chamber; a piston installed to operate up and down in an assembly hall formed in the housing to compress fuel in the chamber to a high pressure; a cylinder forming a gap between an inner circumferential surface and the piston and guiding reciprocation of the piston; and a support member seated on a stepped surface of the housing to surround an outside of the cylinder and configured to elastically support the housing and the cylinder, thereby reducing friction while preventing fuel leakage between the piston and the cylinder.

A method to control a fuel pump for a direct injection system provided with a common rail comprising the steps of calculating the objective fuel flow rate to be fed by the high pressure pump to the common rail instant by instant to have the desired pressure value inside the common rail; comparing the objective fuel flow rate with the maximum flow rate that can be delivered by the high pressure pump; and, based on the comparison between the objective fuel flow rate and the maximum flow rate that can be delivered by the high pressure pump, controlling the high pressure pump so as to alternate operating cycles of the high pressure pump with the maximum flow rate that can be delivered and idle operating cycles of the high pressure pump.

A fuel line check valve system and a fuel system that includes the fuel line check valve system are described. The fuel line check valve system may prevent flow into a fuel system that is generated via a vacuum in the fuel system. The fuel line check valve system may also remain in an open state after it is open via a reduced pressure.

In a mounting tool for mounting an injector on a cylinder head of an engine by being engaged with the injector connected to a fuel pipe, and urging the injector toward the cylinder head, a first band portion has a ring shape so as to surround an outer circumference of the injector, and is disconnected in a circumferential direction by a slit. A second band portion has a ring shape so as to surround the outer circumference of the injector, is disconnected in the circumferential direction by a slit, and is arranged adjacent to the first band portion in an axial direction. Plural elastic band portions connect the first band portion and the second band portion in the axial direction. The mounting tool is made of a single metallic plate.

A fuel injector assembly with a fuel injector and a coupling device is disclosed. The coupling device includes a fuel injector cup, a plate element, one or more screws and a wing clip. The plate element includes at least one through-hole for fixedly coupling the fuel injector cup with the plate element by the screw or screws respectively, so that the fuel injector cup, the plate element and the screw(s) are positionally fixed with respect to each other. The wing clip is arranged at least partly around the fuel injector and extends outward in a radial direction such that the screw or screws, respectively, are operable to block a movement of the fuel injector relative to the plate element in a first direction of the central longitudinal axis by mechanical interaction with the wing clip.

A high-pressure pump includes: a low-pressure chamber, into which low-pressure fuel discharged from a low-pressure pump flows; a pressurizing chamber, which pressurizes the low-low-pressure fuel; and a leak chamber, into which leaked fuel from the pressurizing chamber flows. The leaked fuel of the leak chamber is suctioned into and is pressurized in the pressurizing chamber together with the low-pressure fuel of the low-pressure chamber, so that the leaked fuel is discharged to an outside of the high-pressure pump as high-pressure fuel. Furthermore, a suction check valve, which is placed between the low-pressure chamber and the leak chamber, limits backflow of the leaked fuel of the leak chamber to the low-pressure chamber when the high-pressure pump does not supply the high-pressure fuel.

A high-pressure pump includes: a low-pressure chamber, into which low-pressure fuel discharged from a low-pressure pump flows; a pressurizing chamber, which pressurizes the low-low-pressure fuel; and a leak chamber, into which leaked fuel from the pressurizing chamber flows. The leaked fuel of the leak chamber is suctioned into and is pressurized in the pressurizing chamber together with the low-pressure fuel of the low-pressure chamber, so that the leaked fuel is discharged to an outside of the high-pressure pump as high-pressure fuel. Furthermore, a suction check valve, which is placed between the low-pressure chamber and the leak chamber, limits backflow of the leaked fuel of the leak chamber to the low-pressure chamber when the high-pressure pump does not supply the high-pressure fuel.

Disclosed is a method for limiting fuel leakage from at least one injector in an engine of a motor vehicle, the engine being stopped and the motor vehicle ignition circuit being switched off, the injector being supplied with fuel via a fuel rail which is pressurized during operation, the pressurization persisting for a certain period when the engine has been stopped and the ignition circuit switched off, leading to leakage of fuel through the injector. The injection rail is subjected to forced cooling following the stoppage of the engine with the motor vehicle ignition circuit switched off, which is sufficient to reduce the pressure, the forced cooling continuing until the pressure in the rail is close to atmospheric pressure.

Disclosed is a method for limiting fuel leakage from at least one injector in an engine of a motor vehicle, the engine being stopped and the motor vehicle ignition circuit being switched off, the injector being supplied with fuel via a fuel rail which is pressurized during operation, the pressurization persisting for a certain period when the engine has been stopped and the ignition circuit switched off, leading to leakage of fuel through the injector. The injection rail is subjected to forced cooling following the stoppage of the engine with the motor vehicle ignition circuit switched off, which is sufficient to reduce the pressure, the forced cooling continuing until the pressure in the rail is close to atmospheric pressure.

Provided is a protective structure (64) for a fuel pipe (45) extending along the intake side of an engine main body (9) under an intake manifold (20). A protective member (61) is placed in front of the fuel pipe. The protective member includes a pair of legs (64, 65) secured to the intake side of the engine main body, a main body (63) extending from the legs upward in an arcuate manner along a front side of the fuel pipe and bent rearward in an upper part thereof, and an abutting projection (63G) extending from an upper end of the main body and projecting upward and rearward. A fastening member (26, 27) is passed through a flange of the intake manifold, and includes an engagement feature (36) positioned behind a free end of the abutting projection. The protective member minimizes the loading transmitted to the fuel pipe at the time of a vehicle crash.