摘要:
A fuel injector includes an injector body with a plunger bore that opens to a nozzle outlet. A plunger having a pressure face and a side surface is positioned to reciprocate in the plunger bore between an advanced position and a retracted position. A portion of the plunger bore and the plunger define a fuel pressurization chamber that opens to the nozzle outlet. A needle valve is positioned in the injector body adjacent the nozzle outlet and is moveable between an open position which opens the nozzle outlet and a closed position in which the nozzle outlet is closed to the fuel pressurization chamber. An O-ring is in contact with the side surface of the plunger and the plunger bore on the injector body and serves to seal against fuel leakage past the plunger. Pressure acting on the O-ring is attenuated by providing either a pressure accumulation volume between the pressure face end of the plunger and the O-ring and/or a pressure release passage that opens the plunger bore to a low pressure return line below the O-ring.
摘要:
A valve-closed-orifice (VCO) spray tip having an internal tip seat and one or more fuel spray orifices. The thickness of the tip in the wall portion defining the internal tip seat and upstream entrance of each orifice is made less than that of previously known VCO tips. The length to diameter ratio of each orifice is also relatively smaller than that of previously known VCO tips. Advantages of the thinner wall portion include improved fuel injection spray characteristics as well as reduced cost of forming orifices through the tip.
摘要:
A valve-closed-orifice (VCO) spray tip having an internal tip seat and one or more fuel spray orifices. The thickness of the tip in the wall portion defining the internal tip seat and upstream entrance of each orifice is made less than that of previously known VCO tips. The length to diameter ratio of each orifice is also relatively smaller than that of previously known VCO tips. Advantages of the thinner wall portion include improved fuel injection spray characteristics as well as reduced cost of forming orifices through the tip.
摘要:
An improved fuel injector nozzle employs a hydraulic spring which controls displacement of a needle check to provide a desired rate of fuel flow through an injector orifice.
摘要:
In a hydraulically-actuated electronically-controlled unit injector, the viscosity of the actuating fluid used to actuate the unit injector varies with ambient temperature and affects the magnitude of pressure drops in the actuating fluid circuit. Such variations in viscosity affect the magnitude of the fuel delivery command pulsewidth and/or actuating fluid pressure required for engine startup versus that required for normal engine operation. The present invention provides an improved hydraulically-actuated electronically-controlled unit injector and methods of operation which compensate for variations in the viscosity of the actuating fluid used to hydraulically actuate a piston. The stroke of the piston is controlled electronically and/or mechanically in order to achieve an appropriate amount of fuel injection.
摘要:
The disclosure describes an engine system having liquid and gaseous fuel systems, each of which injects fuel directly into an engine cylinder. A controller monitors and controls engine operation in a normal mode, during which the engine produces rated power, and in a limp-home mode, which is used when an abnormal operating condition of the gaseous fuel system is present. During limp-home mode operation, the engine uses more liquid fuel and less or no gaseous fuel relative to the normal mode, and produces power that is less than rated power.
摘要:
A metallic fuel system component includes an internal surface and an external surface. The metallic fuel system component is made by inducing compressive residual stress in only a portion of the internal surface of the metallic fuel system component by transmitting a laser shock wave through the metallic fuel system component from the external surface to the internal surface.
摘要:
Mixing a pumped fluid with a lubrication fluid within a pump can undermine the lubricity of the lubrication fluid. In order to reduce mixing of fluids within a pump of the present disclosure, a pump is provided that comprises a housing, a piston, a first annulus, and a second annulus. The housing includes an inlet for the pumped fluid, an inlet for the lubrication fluid provided at a first pressure, and a piston bore fluidly coupled to the inlet for the pumped fluid. The piston is moveable within the piston bore. The first annulus is fluidly coupled to the inlet for the lubrication fluid. The second annulus is configured to be fluidly coupled to a drain circuit provided at a second pressure less than the first pressure. The first annulus and the second annulus are located along the length of the piston bore.
摘要:
A component includes a transmission arrangement for transmitting a force between an actuator and a control valve. The transmission arrangement includes a post that is associated with the actuator. The control valve is displaceable to an open position from a closed position when an opening force is applied to the control valve that is greater than a closing force provided to the control valve. The transmission arrangement is disposed in the component between the post and the control valve actuator and arranged to mechanically transmit by physical contact an actuator force from the post to the control valve when the post begins to travel towards the extended stroke position, and hydraulically amplify the actuator stroke between the post and the control valve when the post travels from the retracted stroke position to the extended stroke position.
摘要:
A method of purging fuel supply components for a combustion chamber of a regeneration assembly is disclosed. A regeneration cycle is performed during which fuel is supplied from a fuel source to the combustion chamber with fuel supply components including a fuel supply circuit and at least one fuel injector unit. At least a first purging cycle is initiated to purge residual fuel from the fuel supply components. During the purging cycle, a flow of purging gas is directed to the at least one fuel injector unit to purge residual fuel from the at least one fuel injector unit. Also during the purging cycle, a flow of purging gas is directed to the fuel supply circuit to purge at least a portion of the fuel in the fuel supply circuit toward the fuel source.