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EP-4741659-A2 - COMPACT OPPOSED PUMP

EP4741659A2EP 4741659 A2EP4741659 A2EP 4741659A2EP-4741659-A2

Abstract

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.

Inventors

  • BENHAM, ERIC
  • UNAL, Mustafa
  • BENSON, DONALD
  • MAGNUSON, Samuel
  • MYSER, Benjamin

Assignees

  • Cummins-Scania HPCR System, LLC

Dates

Publication Date
20260513
Application Date
20200311

Claims (14)

  1. A high-pressure fuel pump (100) comprising: a housing (104); a camshaft assembly (110) disposed through the housing (104), the camshaft assembly (110) having an offset lobe (114) and a cam ring (112) encircling the offset lobe (114); a first modular barrel unit (106a) coupled to a first side of the housing (104); and any one of a passive inlet metering valve (102e), an active inlet metering valve (102c), and a hybrid active inlet metering valve (102d) coupled to the housing (104), characterized in that the first modular barrel unit (106a) includes: a module body (200) defining: a first opening (202) configured to receive an inlet valve (103), a second opening configured to receive a plunger (108), a channel (208) configured to house an outlet check valve (206), and a modular pathway (204) configured to align with at least one fuel pathway (150) of the housing (104) of the high pressure pump (100); a plunger (108) disposed in the second opening; and an outlet check valve (206) disposed within the channel (208).
  2. The high-pressure fuel pump (100) of claim 1, comprising: a second modular barrel unit (106b) disposed on a second side of the housing (104) opposite from the first side; wherein the first modular barrel unit (106a) and the second modular barrel unit (106b) are positioned within a first common plane, the second modular barrel unit (106a) having a second center axis (D) offset from a first center axis (C) of the first modular barrel unit (106a).
  3. The high-pressure fuel pump (100) of claim 2, wherein the plunger (108) comprises a first plunger (108a) disposed within the first barrel unit (106a) corresponding with the first center axis (C) and a second plunger (108b) disposed within the second barrel unit (106b) corresponding with the second center axis (D), wherein the first plunger (108a) and the second plunger (108b) are in contact with the cam ring (112) of the camshaft assembly (110).
  4. The high-pressure fuel pump (100) of claim 3, further comprising a first spring (116a) positioned around the first plunger (108a) within the first barrel unit (106a), the first spring (116a) configured to bias the first plunger (108a) toward the camshaft assembly (110), and a second spring (116b) positioned around the second plunger (108b) within the second barrel unit (106b), the second spring (116b) configured to bias the second plunger (108b) toward the camshaft assembly (110).
  5. The high-pressure fuel pump (100) of claim 2, further comprising: a third barrel unit (106c) disposed on a third side of the housing (104), the third barrel unit (106c) having a third center axis (E); and a fourth barrel unit (106d) disposed on a fourth side of the housing (104) opposite from the third side, the fourth barrel unit (106d) having a fourth center axis (F); wherein the third barrel unit (106d) and the fourth barrel unit (106e) are positioned within a second common plane and the third center axis (E) is offset from the fourth center axis (F).
  6. The high-pressure fuel pump (100) of claim 5, wherein the first barrel unit (106a), the second barrel unit (106b), the third barrel unit (106c), and the fourth barrel unit (106d) are equally disposed around a perimeter (121) of the housing (104).
  7. The high-pressure fuel pump (100) of claim 2, wherein: the camshaft assembly (110) has a centerline point (118) defined by a central longitudinal axis (A) of the camshaft assembly (110) around which the camshaft assembly (110) is configured to rotate and the first center axis (C) and the second center axis (D) are offset from the centerline point (118) of the camshaft assembly (110).
  8. The high-pressure fuel pump (100) of claim 7, wherein the first center axis (C) and the second center axis (D) are offset from each other.
  9. The high-pressure fuel pump (100) of claim 7, further comprising: a third barrel unit (106c) disposed on a third side of the housing (104), the third barrel unit (106c) having a third center axis (E); and a fourth barrel unit (106d) disposed on a fourth side of the housing (104) opposite from the third side, the fourth barrel unit (106d) having a fourth center axis (F); wherein the third center axis (E) and the fourth center axis offset (F) from the centerline point (118) of the camshaft assembly (110).
  10. The high-pressure fuel pump (100) of claim 9, wherein the first barrel unit (106a) and the second barrel unit (106b) are in a first common plane and the third barrel unit (106c) and the fourth barrel unit (106d) are in a second common plane.
  11. The high-pressure fuel pump (100) of claim 1, further comprising a second modular barrel unit (106b) coupled to the housing on a second side of the housing opposite from the first side, the first modular barrel unit (106a) and the second modular barrel unit (106b) are positioned within a first common plane.
  12. The high-pressure fuel pump (100) of claim 11, further comprising a third modular barrel unit (106c) coupled to the housing (104) on a third side of the housing (104) and a fourth modular barrel unit (106d) coupled to the housing (104) on a fourth side of the housing (104) opposite from the third side, the third modular barrel unit (106c) and the fourth second modular barrel unit (106d) positioned within a second common plane.
  13. The high-pressure fuel pump (100) of claim 11, wherein the plunger includes plungers (108a, 108b) disposed within each of the first modular barrel unit (106a) and the second modular barrel unit (106b) in contact with the camshaft assembly (110), wherein the plungers (108a, 108b) contacts the cam ring (112) of the camshaft assembly (110) at a point offset from the centerline point of the camshaft assembly (110).
  14. A modular barrel unit (106) comprising: a module body (200) defining: a first opening (202) configured to receive an inlet valve (103) of at least one of a passive inlet metering valve (102e), an active inlet metering valve (102c), and a hybrid active inlet metering valve (102d); a second opening configured to receive a plunger (108); a channel (208) configured to house an outlet check valve (206); and a modular pathway (205) configured to align with at least one fuel pathway (150) of a high-pressure fuel pump (100); a plunger (108) disposed within the second opening; and an outlet check valve (206) disposed within the channel (208).

Description

TECHNICAL FIELD OF THE PRESENT DISCLOSURE The present invention generally relates to a compact eccentric opposed pump, and more particularly, to an opposed pump having offset pumping elements to lighten torque load on a camshaft. BACKGROUND OF THE PRESENT DISCLOSURE High-pressure fuel pumps are common components of fuel systems for internal combustion engines, especially in diesel engines. High-pressure pumps often receive fuel from a low-pressure system before entering a common rail and ultimately the engine via fuel injectors. The fuel is then compressed and exits the pump. Each of these actions are initiated through movement of a plunger controlled by rotation of a camshaft. For example, in high-pressure pumps, fuel is drawn through a fuel inlet as the plunger is lowered relative to a respective barrel containing the plunger. When the plunger then moves upwards, the fuel is compressed, increasing the pressure of the fuel. The fuel then exits the pump to enter the common rail or another fuel system component. Typically, fuel pumps are created by drilling bores into a monolithic block to create pumping units in a linear arrangement, which has cost and manufacturing challenges. Significant cost savings and replacement ease can be achieved using modular barrel units which can be used across a number of fuel pump types, as well as by using light weight, non-load-bearing housing. Furthermore, a space-saving fuel pump may be more easily used across engine sizes and types. SUMMARY OF THE DISCLOSURE 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. In an exemplary embodiment of the present disclosure, a high-pressure pump is disclosed. The high-pressure pump comprises: a housing; a camshaft assembly disposed through the housing and having an offset lobe and a cam ring encircling the offset lobe; a first barrel unit disposed on a first side of the housing, the first barrel unit having a first axis; and a second barrel unit disposed on a second side of the housing opposite from the first side, wherein the first barrel unit and the second barrel unit are positioned within a first common plane. The second barrel unit has a second axis offset from the first axis. The high-pressure pump may further comprise a first plunger disposed within the first barrel unit corresponding with the first axis and a second plunger disposed within the second barrel unit corresponding with the second axis, the first plunger and the second plunger in contact with the cam ring of the camshaft assembly. The high-pressure pump may further comprise a first spring positioned around the first plunger configured to bias the first plunger toward the camshaft assembly and a second spring positioned around the second plunger configured to bias the second plunger toward the camshaft assembly. The high-pressure pump may further comprise a third barrel unit disposed on a third side of the housing, the third barrel unit having a third axis, and a fourth barrel unit disposed on a fourth side of the housing opposite from the third side, the fourth barrel unit having a fourth axis, wherein the third barrel unit and the fourth barrel unit are positioned within a second common plane and the third axis is offset form the fourth axis. The first barrel unit, the second barrel unit, the third barrel unit, and the fourth barrel unit may be equally disposed around a perimeter of the housing. In another exemplary embodiment of the present disclosure, a high-pressure pump is disclosed. The high-pressure pump comprises: a housing; a camshaft assembly disposed through the housing, the camshaft having a centerline point, an offset lobe, and a cam ring encircling the offset lobe; a first barrel unit disposed on a first side of the housing, the first barrel unit having a first axis; and a second barrel unit disposed on a second side of the housing opposite from the first side, the second barrel unit having a second axis, the first axis and the second axis offset form the centerline point of the camshaft assembly. The first axis and the second axis may be offset from each other. The first barrel unit and the second barrel unit may be modular barrel units, and the pump may further comprise any one of a passive inlet metering valve, an active inlet metering valve, and a hybrid active inlet metering valve. The high-pressure pump may further comprise a third barrel unit disposed on a third side of the housing, the third barrel unit having a third axis; and a fourth barrel unit disposed on a fourth side of the housing opposite from