A discharge valve includes: a valve main body that slidably contacts an inner peripheral wall of a tubular portion; and a primary passage that is formed at the valve main body and is located between the valve main body and the inner peripheral wall of the tubular portion. A stopper includes: a stopper main body that is formed separately from the tubular portion while the stopper main body is located on a side of the discharge valve that is opposite to the discharge valve seat; a movement limit surface that is configured to limit movement of the discharge valve in a direction away from the discharge valve seat; and a secondary passage that is formed at the stopper main body.

Disclosed is a method for estimating an angular position of top dead center for a high-pressure fuel injection pump that forms part of a system for injecting fuel into a motor vehicle engine, the pump including at least one piston moving in a chamber between the top and the bottom dead center, the pump being equipped with a digital control valve for controlling a quantity of fuel, an electrical current being applied to the digital valve as it closes then removed in order to open the digital valve, a movement of the digital valve in the direction of opening creating an induced current which makes it possible to detect a position of start-of-opening of the digital valve. An instant at which the pump piston passes through top dead center is estimated as a function of an instant at which the position of start-of-opening of the digital valve appears.

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 fuel pump includes an electromagnetically driven intake valve mechanism, a pump housing, a discharge valve, an opening, a seal member, and a first relief passage. The relief valve mechanism has a relief valve, a relief valve seat contacting the relief valve when the relief valve is closed and a relief spring biasing the relief valve against the relief valve seat. A second relief passage, communicating the first relief passage and a hole formed in the relief seat, is formed between the seal member and the relief valve seat. The relief valve seat, the relief valve, and the relief spring are arranged in this order beginning from the open end side.

Various embodiments include a method for adjusting an initial attenuation current for an injection valve comprising: moving a piston to a TDC; while moving the piston, closing an inlet valve; expelling the fluid; moving the piston away from TDC and applying an attenuation current to an electromagnet with the inlet valve still closed; switching a source for the attenuation current off; detecting an induction pulse resulting from an opening movement of the inlet valve by monitoring a current intensity signal of a subsequent decay in the current; adjusting a current intensity over a plurality of pump cycles to a current intensity level; checking for each current intensity level whether a time profile of the induction pulse satisfies a predetermined detention criterion; and when the detention criterion is satisfied, adjusting the current intensity level for future pump cycles to a lower current intensity level than the most recent level.

A pump includes a pump body having an admission valve movable therein to alternately block and unblock a valve seat to connect a low pressure space to a pumping chamber. A control valve is positioned fluidly between a control chamber and the low pressure space, and moves between a closed position where the control chamber receives high pressure for hydraulically actuating the admission valve, and an open position where the control chamber is connected to the low pressure space to enable closing of the admission valve. The pilot actuation of the admission valve produces a greater travel distance and efficiency than what might be available with certain other actuating mechanisms.

This plunger pump includes a pressurization chamber that has a tubular inner circumferential wall and a plunger that has a substantially cylindrical outer circumferential surface. The inner circumferential wall has, in a part thereof in a circumferential direction about an axis of the plunger, a suction opening, which communicates with the pressurization chamber and is for introducing a fuel into the pressurization chamber. The inner circumferential wall is formed with an enlarged gap portion having a larger dimension than a dimension, at a position of the suction opening, from the outer circumferential surface of the plunger to an inner circumferential surface of the inner circumferential wall along a radial direction of the plunger, in at least a part of the inner circumferential wall at a position away from the position of the suction opening in the circumferential direction.

A circuit and a method for a digital inlet valve having a shutter moveable between a closed and an open position and actuated by a linear electromagnetic actuator including a movable needle located inside a coil winding connected to a power source by a first electronic switch. An electric current is supplied to the coil winding. A parameter indicative of a movement of the needle is monitored. The electric current supply is adjusted when the monitored parameter exceeds a predetermined value.

The invention relates to an electromagnetically actuable intake valve for a high-pressure pump of a fuel injection system, in particular of a common-rail injection system, comprising a reciprocating valve closure element (2) that engages with a valve seat (1) and is loaded in the closing direction by the spring force of a valve spring (3) which is supported on a spring plate (4) connected to the valve closure element (2), further comprising a reciprocating armature (6) that engages with an electromagnet (5) and is loaded in the direction of the valve closure element (2) by the spring force of an armature spring (7) which is larger than that of the valve spring (3). According to the invention, the spring plate (4) has a first abutment face (9) for limiting the opening travel of the valve closure element (2) and a second abutment face (10) for mechanically coupling to the armature (6). The invention also relates to a high-pressure pump having such an intake valve.

A high-pressure fuel supply pump in which a relief valve mechanism is not detached by a force generated by a differential pressure between an inlet side and an output side of a relief valve mechanism is obtained. According to the present invention, in order to obtain the high-pressure fuel supply pump, the relief valve mechanism of the high-pressure fuel supply pump is oriented from a downstream side of a discharge valve to an upstream side of the discharge valve, and the output side of the relief valve mechanism is inserted from the upstream side of the discharge valve into the pump housing, and the relief valve mechanism is fixed with press fitting. Therefore, a force exerted by the differential pressure between the inlet side pressure and the output side pressure of the relief valve mechanism is exerted in a direction in which the relief valve mechanism is inserted, so that the relief valve mechanism can be prevented from being detached.