Abstract:
A unit pump (10) is provided with a bleed port (12) spaced from the main injection port (14). The bleed port (12) improves the rate shape of injection through an associated fuel injector by slowing the initial rate of injection. The bleed port (12) permits shifting of the engine speed at which speed advance occurs. The bleed port (12) also flattens the fuel backup curve. Altering the cross section flow area (18) of the bleed port, axial spacing between the bleed port and inlet port (20) permit the designer to vary (or even eliminate) the impact of the bleed port (12) on the unit pump (10) performance.
Abstract:
A fuel injection system (18) is calibrated as an assembled system. The fuel injection system (18) includes a unit pump (10) a cam follower (24), a joined fuel injection line (14) and injection nozzle (16). The fuel injection system (18) is mounted to a test stand an is subsequently calibrated to a specified fuel delivery and timing. The relative positions of the unit pump (10) and fuel injection nozzle (16) are fixed during calibration. The assembled fuel injection system is packaged and delivered so that the calibrated system can be installed in the relative positions fixed during calibration.
Abstract:
A unit pump (10) is provided with a bleed port (12) spaced from the main injection port (14). The bleed port (12) improves the rate shape of injection through an associated fuel injector by slowing the initial rate of injection. The bleed port (12) permits shifting of the engine speed at which speed advance occurs. The bleed port (12) also flattens the fuel backup curve. Altering the cross section flow area (18) of the bleed port, axial spacing between the bleed port and inlet port (20) permit the designer to vary (or even eliminate) the impact of the bleed port (12) on the unit pump (10) performance.
Abstract:
A fuel injection system is calibrated as an assembled system. The fuel injection system includes a unit pump, cam follower, and joined fuel injection line and injection nozzle. The fuel injection system is mounted to a test stand and calibrated to a specified fuel delivery and timing. The relative positions of the unit pump and fuel injection nozzle are fixed during calibration. The assembled fuel injection system is packaged and delivered so that the calibrated system is installed in the relative positions fixed during calibration.