Various embodiments include a check valve for a high-pressure component in a fuel injection system comprising: a valve housing with a valve hole having an inner diameter; a valve seat and a sealing element arranged in the valve hole; and a coil spring pushing the sealing element toward the valve seat along a longitudinal axis of the valve hole. The coil spring includes a plurality of coil turns each having an outer diameter. In a non-assembled state of the check valve, the outer diameter of at least one of the coil turns is greater than the inner diameter of at least a portion of the valve hole, so that in an assembled state of the check valve, the coil spring is secured in a force-fitting manner in the valve hole.

An isolation mechanism for isolating a submerged pump in a storage vessel, where the isolation mechanism comprises a primary valve member and a secondary valve member, which are both biased in a fail-closed position. The isolation mechanism allows for redundancy for safety and reliability, and can be operated externally of the storage vessel. Furthermore, the isolation mechanism comprises venting and purging devices for safe operation of removal and installation of the pump in the storage vessel.

A high-pressure fuel supply pump including an electromagnetically driven intake valve is configured such that a pressure equalizing hole is provided in the valve stopper positioned between the valve and a pressurizing chamber. The pressure equalization hole connects a spring storage space, provided between a valve and a valve stopper, with a surrounding fluid passage. The high-pressure fuel supply pump is further configured such that an opening of the pressure equalizing hole at the spring storage chamber side is open at a position at the inner side of a diameter of the spring. Since the pressure in the pressurizing chamber can be introduced into the inner side of the spring without traversing the spring, the unstable behavior of the spring or the valve due to the introduced pressure eliminated. Since the force applied to the valve when the valve closes is stabilized, the closing timing of the valve is stable.

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.

The disclosed inlet check valve is used in a high pressure fuel pump and is comprised of a valve member integrally connected to a valve stem which is coupled to an inlet valve armature. The valve member has a stroke along an axis between an open position and a closed position. An inlet valve solenoid generates a magnetic field in an inlet valve pole to attract the inlet valve armature and move the valve member from the open position to the closed position. In the open position, the valve member contacts an inlet valve stop and a gap greater than the stroke of the valve member is defined along the axis between the inlet valve armature and the inlet valve pole. In the closed position, an inlet valve seat mates with the valve member and an armature gap remains between the inlet valve armature and the inlet valve pole.

The disclosed integrated outlet check valve and pressure relief valve are used in a high pressure fuel pump including a pumping chamber and an outlet fitting defining an outlet passage to a common rail. The pressure relief valve comprises a movable pressure relief valve shuttle including a pressure relief valve surface configured to mate with a pressure relief valve seat in a closed position. The pressure relief valve shuttle moves from the closed position to an open position when pressure in the common rail exerts a force greater than the bias of a pressure relief valve spring. The pressure relief valve shuttle also includes an outlet check valve seat configured to mate with an outlet check valve ball in a closed position. The outlet valve ball moves from the closed position to an open position when pressure in the outlet passage is less than pressure in the pumping chamber.

Provided is a high-pressure fuel pump that ensures oil tightness even at high fuel pressure and has a small and lightweight inexpensive discharge valve structure. Therefore, a high-pressure fuel pump according to the present invention includes: a discharge valve arranged on a discharge side of a pressurizing chamber; a discharge valve seat on which the discharge valve is seated; and a facing member configured independently as a separate member from the discharge valve seat and located on an opposite side of the discharge valve seat with the discharge valve interposed therebetween, in which a stroke direction regulating portion that regulates displacement of the discharge valve in a stroke direction is formed on a tapered surface of the facing member.

A method of modifying an existing valve assembly has the step of placing a supplemental sleeve within a housing. The housing has a housing inlet window and a housing outlet window, and the supplemental sleeve has a sleeve inlet window and a sleeve outlet window. The method includes the step of placing an existing piston/sleeve set within the supplemental sleeve. A spool valve is also disclosed.

The invention relates to a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine, comprising at least one cylinder (14), a piston (15) which is displaceably arranged in the cylinder (14), and a pressure valve (30) for selectively controlling the supply of fuel to the internal combustion engine, wherein the pressure valve (30) has a closure part (38, 46, 51) provided with a cavity (44, 49, 53) that opens to the outside on an end surface (43, 48, 52) facing the piston (15) of the closure part (38, 46, 51).

A high pressure pump is disclosed. The high pressure pump comprises a compression chamber having an inlet for connecting to a fluid supply to intake a fluid, and an outlet, an inlet check valve between the compression chamber and the inlet, a digital inlet valve between the compression chamber and the inlet check valve, a variable volume chamber connected to the compression chamber through a manifold and the digital inlet valve, and a plunger or piston configured to compress the fluid in the compression chamber and the variable volume chamber.