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.

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.

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.

Responsiveness is improved in valve opening and valve closing of an electromagnetically driven intake valve unit in which a valve is provided on a pressurizing chamber side of a valve seat. The valve includes an annular abutting surface that abuts the valve seat to shut off a fuel intake passage and a bottomed cylindrical part provided at an inner peripheral part of the annular abutting surface. The bottomed cylindrical part is inserted into a fuel introduction hole formed in the valve housing inside the valve seat, and the outer surface of an end part of the bottomed cylindrical part is exposed to fuel in a low pressure fuel chamber provided upstream of the fuel introduction hole.

A high-pressure fuel supply pump includes a plunger, a valve member, a valve seat, a pressurizing chamber, and a fuel passage. The fuel passage includes a gap passage portion formed in a gap between the valve seat and the valve member. The fuel passage also includes a bent passage portion extending in a bent direction with respect to the gap passage portion, on the downstream side of the gap passage portion. The inner surface of the valve member, on a side thereof that faces the valve seat, has a convex shape in an area of the valve member that is between the bent passage portion and the gap passage portion.

A quantity control valve comprises a valve needle configured to move in an axial direction, a damping chamber having a wall, and a valve element delimiting the damping chamber. The valve needle is configured to move the valve element in an opening direction. A gap is defined between the wall of the damping chamber and the valve element. The gap has at least one recess and connects the damping chamber to a flow duct.

A common rail fuel injection device includes first and second flow rate regulating valves for regulating a delivery volume of a pressurized fuel feed pump that feeds pressurized fuel to a common rail, a pressure reducing valve for reducing a common rail pressure, and a control device. The control device for the common rail fuel injection device includes a first drive controlling unit that controls a first electromagnetic driving unit for the second flow rate regulating valve and a second electromagnetic driving unit for the pressure reducing valve, and a second drive controlling unit that controls a third electromagnetic driving unit for the first flow rate regulating valve. The first drive controlling unit prohibits a drive instruction from being sent to the second flow rate regulating valve when the first drive controlling unit sends a drive instruction to the pressure reducing valve.

Method to control an electromagnetic actuator of an internal combustion engine, in particular for a fuel pump of a direct-injection system; wherein the electromagnetic actuator is controlled by an electric current pulse of the Peak&Hold type, i.e. subdivided into a peak phase and a hold phase; the method includes acquiring the initial duration of the peak phase, during which a peak control current is to be supplied to the electromagnetic actuator to control the movement of a component of the electromagnetic actuator moving towards a position defined by a limit stop; and determining the duration of the peak phase by progressively decreasing the initial duration of the peak phase by a first change.

Systems and methods are provided herein for tracking degradation of a high-pressure fuel pump. In one example, a fuel system controller is configured to receive an output pressure signal from a pressure sensor, transform the output pressure signal to the frequency domain to generate frequency content of the output pressure signal, and diagnose a condition of a fuel pump based at least in part on the frequency content of the output pressure signal, the fuel pump fluidly coupled to a fuel injector via a common fuel rail, and the fuel injector is operable to inject fuel to a cylinder of an engine.

In a fuel pump that includes a pump housing (10) that has fuel passages (11a, 11b), a plunger (17) that is movably housed in the pump housing (10), a fuel pressurizing chamber (15) that is formed in the pump housing (10) and draws in fuel via one of the fuel passages (11a) that is on the intake side of the fuel pressurizing chamber (15), pressurizes the fuel that has been drawn in, and discharges the pressurized fuel via the other fuel passage (11b) that is on the discharge side of the fuel pressure chamber (15), in response to movement of the plunger (17), and valve elements (12, 14, 16) that are arranged in the fuel passages (11a, 11b) near the fuel pressurizing chamber (15), each of the valve elements (12, 14, 16) has a reed valve body (41, 42, 43; 74, 75, 76) arranged in the fuel passage (11a) on the intake side of the fuel pressurizing chamber (15) or the fuel passage (11b) on the discharge side of the fuel pressurizing chamber (15); and an operating member (21) that applies operating force in at least one of a valve opening direction or a valve closing direction to the reed valve body (41, 42, 43; 74, 75, 76) is provided in the pump housing (10).