Compact opposed pump

A high-pressure fuel pump comprising:

• a housing including at least one fuel pathway opening at a housing surface of the housing;
• a camshaft assembly disposed through the housing, the camshaft assembly having a rotation axis, an offset lobe, and a cam ring encircling the offset lobe;
• a first barrel set including a first barrel unit and a second barrel unit disposed on opposite sides of the housing, the first barrel unit having a first center axis offset from a second center axis of the second barrel unit;
• a second barrel set including a third barrel unit and a fourth barrel unit disposed on opposite sides of the housing, the third barrel unit having a third center axis offset from a fourth center axis of the fourth barrel unit,
• wherein each of the first center axis, the second center axis, the third center axis, and the fourth center axis are offset from the rotation axis of the camshaft assembly and evenly spaced apart around a perimeter of the housing of the high-pressure fuel pump to create a uniform load on the housing and the camshaft assembly,
• wherein each the first barrel unit, the second barrel unit, the third barrel unit, and the fourth barrel unit includes a module body coupled to the housing, each module body including:
• a barrel post having a first opening, and a hybrid active inlet metering valve or an active inlet metering valve mounted to the module body in the first opening, the hybrid active inlet metering valve or the active inlet metering valve including an armature mounted to the module body;
• a second opening extending axially from the first opening and a plunger in the second opening so that the plunger is disposed at least partially in the module body and operatively communicates with the hybrid active inlet metering valve or the active inlet metering valve and the cam ring;
• a channel and an outlet check valve housed in the channel;
• and
• a modular pathway from the first opening through the module body to a module body surface of the module body, the module body surface being mounted on the housing surface of the housing so that the modular pathway is aligned with one of the plurality of openings of the at least one fuel pathway of the housing.

A high-pressure fuel pump comprising:

• a housing including at least one fuel pathway opening at a housing surface of the housing;
• a camshaft assembly disposed through the housing, the camshaft assembly having an offset lobe and a cam ring encircling the offset lobe;
• a first modular barrel unit coupled to a first side of the housing;
• a second modular barrel unit coupled to the housing on a second side of the housing opposite from the first side, wherein the first modular barrel unit and the second modular barrel unit each include a module body coupled to the housing, each module body including:
• a barrel post having a first opening;
• a hybrid active inlet metering valve or an active inlet metering valve disposed in the first opening of the module body thereof and coupled to the housing through the corresponding first modular barrel unit and the second modular barrel unit, the hybrid active meting valve or the active inlet metering valve including an armature disposed on the module body;
• a second opening extending axially from the first opening and a plunger in the second opening so that the plunger is disposed at least partially in the module body and operatively communicates with the cam ring and the hybrid active inlet metering valve or the active inlet metering valve disposed thereon;
• a channel and an outlet check valve housed in the channel;
• and
• a modular pathway from the first opening through the module body to a module body surface of the module body, the module body surface being mounted on the housing surface of the housing so that the modular pathway is aligned with one of the plurality of openings of the at least one fuel pathway of the housing,
• wherein, in the event of failure of one or more components of the first modular barrel unit and the second modular barrel unit, removal of the first modular barrel unit and the second modular barrel unit from the housing also removes the corresponding hybrid active inlet metering valve or the active inlet metering valve disposed thereon so that the corresponding hybrid active metering valve or the active metering inlet valve is replaced by replacing the first modular barrel unit and/or the second modular barrel unit rather than replacing the entire high-pressure fuel pump.

A modular barrel unit comprising:

• an inlet valve that is a hybrid active inlet metering valve, the hybrid active inlet metering valve including an armature;
• and
• a module body configured to be mounted at least partially within a housing of a high-pressure fuel pump, the module body including:
• a barrel post including a first opening configured to receive the inlet valve so that the inlet valve is disposed on the module body;
• a second opening extending axially from the first opening and configured to receive a plunger so that the plunger is disposed at least partially in the module body and operatively communicates with the inlet valve;
• a channel configured to house an outlet check valve;
• a modular pathway from the first opening through the module body to a module body surface that is mounted on a housing surface of the housing in alignment with an opening of at least one fuel pathway of the housing of the high-pressure fuel pump;
• and
• the armature disposed on the module body and further comprising a spring and a spring retainer mounted on the module body, wherein the armature, the spring, and the spring retainer are spaced apart from the barrel post,
• wherein, in the event of failure of one or more components of the modular barrel unit, the modular barrel unit including the hybrid active inlet metering valve disposed thereon is configured to be replaced rather than replacing the entire high-pressure fuel pump.