Locomotive engine with skipfire control system

Abstract

A skipfire control system for use in a locomotive engine includes a plurality of skipfire mechanisms. Each skipfire mechanism is operatively associated with a respective injector rocker arm of the plurality of cylinders of the engine. Each skipfire mechanism includes an actuator movable between an inoperative position wherein the actuator allows the camshaft of the engine to engage and move the associated injector rocker arm to actuate the associated fuel injector, and an operative position wherein the actuator disengages the associated injector rocker arm from the camshaft to prevent the associated rocker arm from actuating the associated fuel injector. A skipfire controller is operatively connected to the skipfire mechanisms and is responsive to an engine operating parameter to actuate selected ones of the skipfire mechanisms to move the actuators thereof to operative positions to prevent actuation of the fuel injectors associated with the selected ones of the skipfire mechanisms.

Description

FIELD OF THE INVENTION [0001] The present invention relates to locomotive engines. More particularly, the present invention relates to the use of skipfiring of the locomotive engine to reduce exhaust emissions and fuel consumption. BACKGROUND AND SUMMARY OF THE INVENTION [0002] At low engine speeds, a locomotive engine does not need to have fuel delivered to all the cylinders to operate. However, in conventional systems, the fuel is continuously delivered to all the cylinders irrespective of engine speed, and this in turn means unnecessary fuel is being wasted, and in turn unnecessary emissions are being generated. [0003] It is known to selectively cut off fuel delivery to a select amount of engine cylinders (called “skipfire” because firing of these cylinders is skipped over), leaving enough cylinders operating to maintain engine speed. This in turn reduces fuel consumption and emissions. Once engine speed picks back up above a predetermined threshold, the system will return to nor...

AI Technical Summary

Benefits of technology

[0003] It is known to selectively cut off fuel delivery to a select amount of engine cylinders (called “skipfire” because firing of these cylinders is skipped over), leaving enough cylinders operating to maintain engine speed. This in turn reduces fuel consumption and emissions. Once engine speed picks back up above a predetermined threshold, the system will return to normal operation and enable fuel delivery to all engine cylinders for delivering full power.

[0007] In accordance with the principles of the present invention, this aspect may be achieved by providing a skipfire control system for use in a locomotive engine including a plurality of fuel injected cylinders, each of the plurality of cylinders having a fuel injector and an injector rocker arm movable to actuate the fuel injector to inject fuel to the associated cylinder. The engine also includes a camshaft engagable with each of the injector rocker arms to move the rocker arms for actuation of the fuel injectors. The skipfire control system comprises a plurality of skipfire mechanisms, each of the plurality of skipfire mechanisms being operatively associated with a respective injector rocker arm of the plurality of cylinders. Each of the plurality of skipfire mechanisms includes an actuator movable between (1) an inoperative position wherein the actuator allows the camshaft to engage and move the associated injector rocker arm to actuate the associated fuel injector, and (2) an operative position wherein the actuator disengages the associated injector rocker arm from the camshaft to prevent the associated rocker arm from being moved by the camshaft to actuate the associated fuel injector. A skipfire controller is operatively connected to the plurality of skipfire mechanisms. The skipfire controller is responsive to an engine operating parameter to actuate selected ones of the plurality of skipfire mechanisms so as to move the actuators thereof to the operative positions to thereby prevent actuation of the fuel injectors associated with the selected ones of the plurality of skipfire mechanisms.

Problems solved by technology

However, in conventional systems, the fuel is continuously delivered to all the cylinders irrespective of engine speed, and this in turn means unnecessary fuel is being wasted, and in turn unnecessary emissions are being generated.

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