摘要:
An injection rate shaping nozzle assembly for a fuel injector is provided which includes a closed nozzle valve element and a rate shaping control device including an injection spill circuit for spilling a portion of the fuel to be injected to produce a predetermined time varying change in the flow rate of fuel injected into a combustion chamber. The spill circuit includes a spill passage integrally formed in the nozzle valve element. The rate shaping control device may include a spill accelerating chamber in formed in the nozzle valve element for creating a rapid increase in the spill flow rate. A spill circuit purge device is provided to remove fuel from the spill circuit and accelerating chamber between each of the injection events thereby ensuring an unimpeded, effective spill fuel flow during the next spill event. The purge device includes a purge passage formed of a predetermined size for restricting the flow of purge gas to ensure sufficient fuel removal from the injection spill circuit while avoiding excessive purge gas flow. The purge passage may include an annular clearance gap formed between the nozzle valve element and the nozzle housing wall, or alternatively, may include an orifice passage formed in the inner portion of the nozzle valve element. An improved method for forming a nozzle valve element having an axial center passage is also disclosed.
摘要:
The improved needle controlled common rail fuel system of the present invention includes split common rails serving respective sets of injectors and a respective high pressure pump associated with each rail. The high pressure pumps reciprocate to cyclically create gradual periods of increasing pressure in the common rail during the advancement stroke of the plunger followed by respective periods of decreasing pressure during the plunger's retraction stroke. The fuel injectors include an injection control valve and a needle control device for creating an injection event during a pumping event by controlling the fuel flow to drain so as to control the fuel pressure forces acting on an injector needle valve element. A flow limiting device is provided to limit the fuel flow from a control volume to drain during an injection event thus reducing parasitic losses while maintaining quick valve closing. The system also includes an improved fuel injector design including an intensification plunger assembly. In addition, a pressure energy recuperation means is provided which utilizes the pressure of the fuel in the common rail and the fuel injectors as a result of the pressure energy stored in the fuel to assist in retraction of the high pressure pump plunger during each pumping event. In addition, a wiring connection harness is provided which permits the connection of an electrically operated fuel delivery device, i.e. injector, to an electrical source simultaneously with the mounting of the fuel delivery device on the engine.
摘要:
An apparatus, system, and method are disclosed for delivering a dosant with engine exhaust. The apparatus includes a flow-rate regulator disposed downstream from an engine exhaust manifold that operates to control a fraction of exhaust from the engine exhaust manifold. The apparatus also includes a doser disposed downstream of the flow-rate regulator that provisions a supply of dosant to the path of the controlled fraction of exhaust, which atomizes, vaporizes, disperses, mixes with, and/or delivers the dosant.
摘要:
A system includes an internal combustion engine receiving intake air from an intake manifold and providing exhaust gases to an exhaust manifold. The system further includes an exhaust gas recirculation (EGR) conduit fluidly coupling the exhaust manifold to the intake manifold. The system includes a conical spring check valve disposed in the EGR conduit, the conical spring check valve having a helically wound spring including a number of turns of decreasing diameter, where each turn progresses axially in a normal flow direction of the EGR from a previous one of the turns. Each of the turns further overlaps a previous one of the turns.
摘要:
A pump component is removed from a port of a suction-side fluid cavity of a high-pressure fluid pump. The pump component performs a pump function for the high-pressure fluid pump. A primary coupler connects to the port. The pump component connects to the primary coupler. A diverter fluid passage diverts a low-pressure fluid from the primary coupler to an auxiliary fluid delivery system. The primary coupler communicates the low-pressure fluid through the pump component and primary coupler to the port.
摘要:
The valve includes a valve element with an internal longitudinal bore and cross-drilled orifices which, in combination with other orifices and restrictions, force balance the valve in an open configuration when attached to a pump assembly in a spilling mode.
摘要:
The high-pressure fluid manifold connection assembly includes a one-piece tube collar with an annular relief cavity that surrounds a high-pressure fluid tube. The tube includes a hole that passes through the tube and which is not aligned with an exit hole in an annular relief cavity of the tube collar.
摘要:
A fuel injection system is disclosed for an internal combustion engine that has multiple combustion chambers and a camshaft which cyclically imparts pressurization energy to and recovers pressurization energy from fuel being supplied to the engine. The fuel injection system includes a plurality of unit injectors, a camshaft linkage which simultaneously reciprocates pressurizing plungers of a set of at least two unit injectors and an interconnecting line which allows selective fluid interconnection between fuel pressurization chambers formed within the unit injectors. The interconnection line allows fluid linkage of the volume of fuel which is simultaneously pressurized and depressurized within the interconnected fuel pressurization chambers of a first set of unit injectors.
摘要:
A strategy for quantifying and compensating for between-engine variations in engine static timing, fuel pump phasing and overall system bandwidth includes a control circuit operable to manage a fuel control system including a high pressure, cyclically operable fuel pump and at least one fuel injector operable to supply fuel to an internal combustion engine from a fuel collection unit. In one embodiment, the strategy of the present invention is operable to determine peak values of the fuel pressure within fuel collection unit and corresponding engine position values for a number of different engine speeds and solve a corresponding model-based system of equations to determine a combined engine static timing and fuel pump phasing error as well as a first overall system bandwidth value. In another embodiment, the strategy of the present invention is operable to determine peak values of the pressure within a combustion chamber of the engine along with associated engine position values for a number of different engine speeds and solve for the engine static timing error alone and/or a second overall system bandwidth value. In yet another embodiment, the two foregoing strategies may be combined to produce separately the first and second bandwidth values as well as the individual engine static timing and fuel pump phasing error values. In any case, the computed error and bandwidth values may be used to improve the accuracy of sampled engine and/or fuel control system parameters as they relate to engine position.
摘要:
An improved plunger and barrel assembly is provided which includes a plunger reciprocally mounted in a cavity formed in the barrel and a leakage flow reduction device positioned in the cavity for reducing fluid leakage flow around the plunger thus increasing system efficiency. The leakage flow reduction device includes a sealing sleeve removably mounted in the cavity between the plunger and the barrel, which includes a bore for slidably receiving the plunger to form an annular clearance gap between the plunger and the bore. The sealing sleeve is designed to resiliently flex in response to fluid pressure forces to reduce the annular clearance gap so as to minimize fluid leakage through the annular clearance gap. The sealing sleeve is formed as a separate piece from the barrel to permit simple, low cost replacement. The sealing sleeve is preferably applied to a fuel pump having a pump plunger for pressurizing fuel in a high pressure chamber.