Compact opposed pump
The present disclosure provides a high-pressure fuel pump having barrel sets comprising offset, opposing barrel units within the same plane and having plungers disposed therein. The high-pressure fuel pump further includes a camshaft having at least one offset lobe and a cam ring encircling the lobe and in contact with the plungers, which translate the rotational movement of the camshaft to longitudinal movement of the plungers, controlling inflow, compression, and outflow of fuel within the pump.
1 . A high-pressure fuel pump comprising:
a housing including at least one fuel pathway with a plurality of openings at a housing surface of the housing;
a camshaft assembly disposed through the housing and having 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 positioned within a first common plane and 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 positioned within a second common plane and 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 barrel unit, the second barrel unit, the third barrel unit, and the fourth barrel unit are separated 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 of 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 mounted to the module body in the first opening, the hybrid 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 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.
2 . The high-pressure fuel pump of claim 1 , wherein the plunger is a first plunger disposed within the first barrel unit corresponding with the first center axis and further comprising a second plunger disposed within the second barrel unit corresponding with the second center axis, wherein the first plunger and the second plunger are in contact with the cam ring of the camshaft assembly.
3 . The high-pressure fuel pump of claim 2 , further comprising a first spring positioned around the first plunger, the first spring configured to bias the first plunger toward the camshaft assembly, and a second spring positioned around the second plunger, the second spring configured to bias the second plunger toward the camshaft assembly.
4 . The high-pressure fuel pump of claim 1 , further comprising a third plunger disposed within the third barrel unit corresponding with the third axis and a fourth plunger disposed within the fourth barrel unit corresponding with the fourth axis, wherein the third plunger and the fourth plunger are in contact with the cam ring of the camshaft assembly.
5 . The high-pressure fuel pump of claim 4 , further comprising a third spring positioned around the third plunger, the third spring configured to bias the third plunger toward the camshaft assembly, and a fourth spring positioned around the fourth plunger, the fourth spring configured to bias the fourth plunger toward the camshaft assembly.
6 . The high-pressure fuel pump of claim 1 , wherein for each module body the hybrid active inlet metering valve is mounted to the corresponding module body and includes a spring and a spring retainer.
7 . The high-pressure fuel pump of claim 1 , wherein:
the camshaft assembly includes a rotation axis; and
each of the first center axis, the second center axis, the third center axis, and the fourth center axis are unique from one another and offset from the rotation axis.
8 . 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.
9 . The high-pressure fuel pump of claim 8 , wherein the plunger is a first plunger disposed within the first barrel unit corresponding with the first center axis and further comprising a second plunger disposed within the second barrel unit corresponding with the second center axis.
10 . The high-pressure fuel pump of claim 9 , further comprising a third plunger disposed within the third barrel unit corresponding with the third axis and a fourth plunger disposed within the fourth barrel unit corresponding with the fourth axis, wherein the third plunger and the fourth plunger are in contact with the cam ring of the camshaft assembly.
11 . The high-pressure fuel pump of claim 8 , wherein the first barrel unit and the second barrel unit are in a first common plane and the third barrel unit and the fourth barrel unit are in a second common plane.
12 . The high-pressure fuel pump of claim 8 , wherein the first barrel unit and the second barrel unit are modular barrel units and the high-pressure fuel pump further comprises the hybrid active inlet metering valve or the active inlet metering valve and the outlet check valve being disposed on the first barrel unit and a second hybrid active inlet metering valve or the active inlet metering valve and a second outlet check valve being disposed on the second barrel unit.
13 . The high-pressure fuel pump of claim 8 , wherein each of the first center axis, the second center axis, the third center axis, and the fourth center axis are unique from one another and offset from the rotation axis.
14 . 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.
15 . The high-pressure fuel pump of claim 14 , wherein the first modular barrel unit and the second modular barrel unit are positioned within a first common plane.
16 . The high-pressure fuel pump of claim 15 , further comprising a third modular barrel unit coupled to the housing on a third side of the housing and a fourth modular barrel unit coupled to the housing on a fourth side of the housing opposite from the third side, wherein the third modular barrel unit and the fourth modular barrel unit are positioned within a second common plane.
17 . The high-pressure fuel pump of claim 14 , wherein the plunger is disposed within the first modular barrel unit and in contact with the camshaft assembly, wherein the plunger contacts the cam ring of the camshaft assembly at a point offset from a rotation axis of the camshaft assembly.
18 . The high-pressure fuel pump of claim 14 , wherein for each module body the hybrid active inlet metering valve or the active inlet metering valve is disposed on the corresponding modular barrel unit, and both the outlet check valve and the hybrid active inlet metering valve or the active inlet metering valve are coupled to the housing via the corresponding modular barrel unit, and the hybrid active inlet metering valve or the active inlet metering valve includes a spring and a spring retainer mounted on the module body of the corresponding modular barrel unit.
19 . 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.