Operating an engine system and fuel system includes energizing a solenoid actuator for a spill valve in a fuel injector in a first engine cycle via a standard waveform to inject a shot of fuel. Operating an engine system and fuel system further includes determining suitability for reduced energy operating of the fuel system, and energizing the solenoid actuator via a reduced energy waveform based on the determining suitability so as to inject one or more shots of fuel in a second engine cycle. The operating methodology and control logic can extend an engine speed range for multi-shot fuel injection in an engine.

A fuel injection valve includes a needle valve that controls communication between a high pressure chamber and an injection hole, a follower valve provided inside a control chamber controlled by fuel pressure inside an intermediate chamber, and an open-close valve that controls communication between a first passage and a low pressure passage and communication between a second passage and the low pressure passage. The fuel injection valve is configured to control the gradient of the fuel injection rate from the injection hole with an improved configuration.

A fuel injection method includes applying a first method current to close a spill valve according to a first method, applying a control valve current to open a control valve, and discontinuing the application of the control valve current to thereby cause the control valve to close. The method also includes applying a second method current to maintain the spill valve closed according to a second method and detecting a timing of a closing of the control valve while applying the second method current according to the second method, the second method being different than the first method.

A fuel injector includes a nozzle having at least one nozzle outlet. A valve needle is moveable with respect to a valve needle seating through a range of movement between a closed position and an open position to control fuel delivery through the at least one nozzle outlet. The movement of the nozzle needle is controlled by fuel pressure within a control chamber. The injector has first and second nozzle control valves for controlling fuel flow into and out of the control chamber to pressurise and depressurise the control chamber, respectively. The first nozzle control valve can operate selectively to place the control chamber in fluid communication with a fuel drain or to place the control chamber in fluid communication with a high pressure supply line. The second nozzle control valve can operate selectively to place the control chamber in fluid communication with a fuel drain.

A fuel injection method includes applying a first method current to close a spill valve according to a first method, applying a control valve current to open a control valve, and discontinuing the application of the control valve current to thereby cause the control valve to close. The method also includes applying a second method current to maintain the spill valve closed according to a second method and detecting a timing of a closing of the control valve while applying the second method current according to the second method, the second method being different than the first method.

A method of injecting fuel with a fuel injector includes applying a spill valve current to close a spill valve and applying a control valve current to move a control valve to an injection position. The method also includes discontinuing the application of the spill valve current to open the spill valve and preventing a return of the control valve to a non-injection position while detecting a timing when the spill valve opens.

A check and flow metering cartridge valve having two flow restriction zones, each zone being disposed adjacent a respective end of a valve chamber containing a check valve member, the zones being serially encountered by flow through the valve, the restriction of the restriction zones together being a majority of the total flow restriction in the valve, each restriction zone producing at least 26% of a total restriction to flow through the valve, the restriction zones maintaining back pressure in the valve chamber when the check valve member is unseated thereby providing damping of the check valve member.

A check and flow metering cartridge valve having two flow restriction zones, each zone being disposed adjacent a respective end of a valve chamber containing a check valve member, the zones being serially encountered by flow through the valve, the restriction of the restriction zones together being a majority of the total flow restriction in the valve, each restriction zone producing at least 26% of a total restriction to flow through the valve, the restriction zones maintaining back pressure in the valve chamber when the check valve member is unseated thereby providing damping of the check valve member.

A control device for a fuel injection valve including a variable lift mechanism of two or more stages is provided. The control device includes an inflection point detection unit for detecting an inflection point from at least one of a drive current when the fuel injection valve is opened or a drive voltage when the fuel injection valve is closed. The control device also includes a drive sensing unit for sensing a drive lift of the fuel injection valve from at least one of an inflection point of a drive current during valve opening operation or a drive voltage during valve closing operation. The control device is configured to limit the command drive lift when the sensed drive lift is different from a command drive lift.

A fuel injection valve includes a needle valve that controls communication between a high pressure chamber and an injection hole, a follower valve provided inside a control chamber controlled by fuel pressure inside an intermediate chamber, and an open-close valve that controls communication between a first passage and a low pressure passage and communication between a second passage and the low pressure passage. The fuel injection valve is configured to control the gradient of the fuel injection rate from the injection hole with an improved configuration.