A high pressure fuel pump includes: a pump body that forms a suction passage and a pressurizing chamber and slidably supports a plunger; and a control valve that opens a connection between the suction passage and the pressurizing chamber in a suction stroke, during which the plunger is driven toward a suction side for suctioning fuel into the pressurizing chamber, while the control valve controls closing timing, at which the connection between the suction passage and the pressurizing chamber is closed by the control valve in a delivery stroke, during which the plunger is driven toward a delivery side for delivering the fuel out of the pressurizing chamber. The pump body forms a release passage that is communicated with the suction passage. The release passage relieves the fuel, which is pressurized by the plunger, from the pressurizing chamber before the closing timing during the delivery stroke.

A high pressure fuel pump includes: a pump body that forms a suction passage and a pressurizing chamber and slidably supports a plunger; and a control valve that opens a connection between the suction passage and the pressurizing chamber in a suction stroke, during which the plunger is driven toward a suction side for suctioning fuel into the pressurizing chamber, while the control valve controls closing timing, at which the connection between the suction passage and the pressurizing chamber is closed by the control valve in a delivery stroke, during which the plunger is driven toward a delivery side for delivering the fuel out of the pressurizing chamber. The pump body forms a release passage that is communicated with the suction passage. The release passage relieves the fuel, which is pressurized by the plunger, from the pressurizing chamber before the closing timing during the delivery stroke.

A fuel pump includes a fuel pump housing with a pumping chamber and an inlet valve bore which extends along an inlet valve bore axis. The inlet valve bore is stepped such that the inlet valve bore includes a shoulder which is traverse to the inlet valve bore axis. A pumping plunger reciprocates within a plunger bore along a plunger bore axis such that an intake stroke of the pumping plunger increases volume of the pumping chamber and a compression stroke of the pumping plunger decreases volume of the pumping chamber. An inlet valve assembly includes a valve seat with a valve seat flow passage extending therethrough, the valve seat abuts the shoulder and is urged toward the shoulder by pressure within the pumping chamber during the compression stroke. The inlet valve assembly also includes a valve member which is moveable between an unseated position and a seated position.

A fuel pump for a direct injection system and having: a main body; a pumping chamber; a piston, which is mounted in a sliding manner on the inside of the pumping chamber; an intake duct, which ends in the pumping chamber; an intake valve, which is arranged along the intake duct; and a flow rate adjustment device provided with a control rod which is coupled to the intake valve and with an electromagnetic actuator which is configured to axially move the control rod. The flow rate adjustment device has a containing element, which houses the electromagnetic actuator, has an open end facing the intake valve, and ends with a “U”-shaped rim which has an outer ring which is arranged around the containing element at a given distance from a cylindrical wall of the containing element. An annular weld (22) is obtained between the main body and the outer ring of the “U”-shaped rim.

A fuel pump for a direct injection system and having: a main body; a pumping chamber; a piston, which is mounted in a sliding manner on the inside of the pumping chamber; an intake duct, which ends in the pumping chamber; an intake valve, which is arranged along the intake duct; and a flow rate adjustment device provided with a control rod which is coupled to the intake valve and with an electromagnetic actuator which is configured to axially move the control rod. The flow rate adjustment device has a containing element, which houses the electromagnetic actuator, has an open end facing the intake valve, and ends with a “U”-shaped rim which has an outer ring which is arranged around the containing element at a given distance from a cylindrical wall of the containing element. An annular weld (22) is obtained between the main body and the outer ring of the “U”-shaped rim.

A fluid filtering device may have a body that include a fluid collection portion, a filtering chamber, and a passthrough bore. The fluid collection portion may be configured to collect fluid supplied to the fluid filtering device. The filtering chamber may be in fluid communication with the fluid collection portion. The filtering chamber may have an entrance portion, an exit portion, and a fluid filter. The filtering chamber may be configured to filter the fluid supplied to the fluid filtering device. The passthrough bore may be in fluid communication with the filtering chamber and may be separate from the fluid collection portion such that fluid flowing from the fluid collection portion flows into the filtering chamber, and the fluid flowing from the filtering chamber flows into the passthrough bore.

A fluid filtering device may have a body that include a fluid collection portion, a filtering chamber, and a passthrough bore. The fluid collection portion may be configured to collect fluid supplied to the fluid filtering device. The filtering chamber may be in fluid communication with the fluid collection portion. The filtering chamber may have an entrance portion, an exit portion, and a fluid filter. The filtering chamber may be configured to filter the fluid supplied to the fluid filtering device. The passthrough bore may be in fluid communication with the filtering chamber and may be separate from the fluid collection portion such that fluid flowing from the fluid collection portion flows into the filtering chamber, and the fluid flowing from the filtering chamber flows into the passthrough bore.

A solenoid valve includes an inner stator and an outer stator that are part of a magnetic circuit. An armature is attracted toward the inner stator when a coil is energized. A spring biases the armature in a direction away from the inner stator. A rod is integrally formed with the armature and integrally reciprocates with the armature. A guide guides reciprocation of the rod. A valve operates by following the rod to open and close a fuel/liquid passage. The spring and sliding portions between the rod and the guide are arranged within a recess portion formed in the inner stator and arranged in parallel to each other while overlapping in the axial direction.

A solenoid valve includes an inner stator and an outer stator that are part of a magnetic circuit. An armature is attracted toward the inner stator when a coil is energized. A spring biases the armature in a direction away from the inner stator. A rod is integrally formed with the armature and integrally reciprocates with the armature. A guide guides reciprocation of the rod. A valve operates by following the rod to open and close a fuel/liquid passage. The spring and sliding portions between the rod and the guide are arranged within a recess portion formed in the inner stator and arranged in parallel to each other while overlapping in the axial direction.

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.