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).

Embodiments relate to a valve arrangement for a fuel injection system, including a valve disc that has a valve opening. A deformable valve sheet that is movable in a movement direction is provided to open and close the valve opening, and a valve shaft of a movement-activation arrangement, provided to activate the movement of the valve sheet, is secured to the valve sheet. The embodiments also relate to a high-pressure pump which includes the valve arrangement.

A high pressure fuel supply pump includes: an electromagnetic suction valve that adjusts an amount of fuel sucked into a pressuring chamber; a discharge valve that discharges the fuel from the pressuring chamber; and a plunger that makes a reciprocating motion in the pressuring chamber. The electromagnetic suction valve includes an electromagnetic coil, a suction valve, and a movable portion that is able to close the suction valve by a magnetic force when the electromagnetic coil is energized. The movable portion includes an anchor that is driven to close the suction valve by the magnetic force and stops at a fixed member, and a rod that is driven with the anchor and is able to move even after the anchor stops. The electromagnetic suction valve includes a first and second springs that bias the suction valve in closed and open direction, respectively, and a third spring in the rod.

The present invention relates to a high pressure fuel pump comprising an inlet channel in connection with a first chamber, through which inlet channel fuel is led to the first chamber, a second chamber arranged in connection with the first chamber, an outlet valve arranged in connection with the second chamber and an inlet valve comprising a piston, with a first end section and a second end section. The piston is moveably arranged with the first end section in a third chamber, and the second end section is moveably arranged between the first chamber and the second chamber. A press element is arranged to act on the piston with a mechanic force, so that the piston strives to be positioned with the second end section closing the connection between the first chamber and the second chamber. The inlet valve is in a closed state and may be controlled via an electromagnetic unit.

The present invention relates to a high pressure fuel pump comprising an inlet channel in connection with a first chamber, through which inlet channel fuel is led to the first chamber, a second chamber arranged in connection with the first chamber, an outlet valve arranged in connection with the second chamber and an inlet valve comprising a piston, with a first end section and a second end section. The piston is moveably arranged with the first end section in a third chamber, and the second end section is moveably arranged between the first chamber and the second chamber. A press element is arranged to act on the piston with a mechanic force, so that the piston strives to be positioned with the second end section closing the connection between the first chamber and the second chamber. The inlet valve is in a closed state and may be controlled via an electromagnetic unit.

A discharge valve of a high-pressure pump is placed in a discharge passage and is openable to enable flow of fuel from a pressurizing chamber to a discharge outlet in response to a fuel pressure difference between the pressurizing chamber side and the discharge outlet side. A relief is placed in a relief passage. The relief passage communicates between a branching portion, which is located on a side of the discharge valve where the discharge outlet is placed in the discharge passage, and a return portion, which merges with a damper chamber. The relief valve is openable to enable flow of the fuel from the branching portion to the return portion in response to a fuel pressure difference between the branching portion side and the return portion side. A discharge passage orifice is placed between the discharge valve and the branching portion in the discharge passage and constricts a flow passage cross-sectional area of the discharge passage.

A discharge valve of a high-pressure pump is placed in a discharge passage and is openable to enable flow of fuel from a pressurizing chamber to a discharge outlet in response to a fuel pressure difference between the pressurizing chamber side and the discharge outlet side. A relief is placed in a relief passage. The relief passage communicates between a branching portion, which is located on a side of the discharge valve where the discharge outlet is placed in the discharge passage, and a return portion, which merges with a damper chamber. The relief valve is openable to enable flow of the fuel from the branching portion to the return portion in response to a fuel pressure difference between the branching portion side and the return portion side. A discharge passage orifice is placed between the discharge valve and the branching portion in the discharge passage and constricts a flow passage cross-sectional area of the discharge passage.

A roller lifter includes a lifter body having a cylindrical peripheral wall and a roller rotatably mounted on the lifter body via a shaft member and brought into contact with a cam. The peripheral wall has an outer periphery formed with a sliding surface which is slid on an inner wall of a cylinder. The lifter body has a rotation stopper formed by outwardly protruding a part of the peripheral wall, and an opening formed in another part of the peripheral wall which another part is radially opposed to the rotation stopper. The opening is open so that the rotation stopper oppositely faces the opening.

A roller lifter includes a lifter body having a cylindrical peripheral wall and a roller rotatably mounted on the lifter body via a shaft member and brought into contact with a cam. The peripheral wall has an outer periphery formed with a sliding surface which is slid on an inner wall of a cylinder. The lifter body has a rotation stopper formed by outwardly protruding a part of the peripheral wall, and an opening formed in another part of the peripheral wall which another part is radially opposed to the rotation stopper. The opening is open so that the rotation stopper oppositely faces the opening.

The error diagnosis device has: an input unit that receives a downstream pressure value and an upstream pressure value, said downstream pressure value being detected on the downstream side of a fuel pump and said upstream pressure value being detected on the upstream side of the fuel pump; and a determination unit that, if the downstream pressure value is less than a preset first threshold value, determines whether or not the upstream pressure value is less than a preset second threshold value. The determination unit determines that an error has occurred further upstream than the fuel pump if the upstream pressure value is less than the second threshold value and determines that an error has occurred in the fuel pump if the upstream pressure value is at least the second threshold value.