US 6,779,506 B1Granted

Engine brake control pressure strategy

AssigneeInternational Engine Intellectual Property Company, LLC

InventorsJames T. Beaucaire, David S. Hlavac, David V. Rodgers

Life of this patent

Estimating the term…

Loading patent…

Abstract

An engine (10) has a hydraulic system (28) that serves both fuel injectors (22) and hydraulic actuators (40) of an engine brake that brakes the engine by controlling exhaust gas flow during engine braking. Pressure of the hydraulic fluid is set by an injection control strategy when a brake control pressure strategy is inactive. When the brake control pressure strategy is active, braking of the engine occurs when hydraulic fluid is delivered to the actuators. The brake control pressure strategy signals pressure of the hydraulic fluid supplied to the one or more actuators that is in excess of a pressure determined by a brake control pressure strategy. The brake control pressure strategy then limits pressure of the hydraulic fluid.

Claims19

Dependent claims

An internal combustion engine comprising:

a fueling system for forcing fuel into engine combustion chambers where the fuel is combusted to power the engine;
an exhaust system through which exhaust gases generated by combustion of fuel in the combustion chambers pass from the engine;
an engine brake system that is associated with the exhaust system to brake the engine by controlling exhaust flow during engine braking and that comprises one or more hydraulic actuators that is or are actuated during braking of the engine by the engine brake system;
a hydraulic system for supplying hydraulic fluid under pressure both to the fueling system for forcing fuel into the combustion chambers and to the one or more actuators;
a control system for controlling various aspects of engine operation, including controlling braking of the engine by selectively communicating hydraulic fluid to the one or more actuators;
and
a fuel injection control strategy in the control system for closed-loop control of injection control pressure to cause injection control pressure to correspond to an injection control pressure set by the fuel injection control strategy;
and
a brake control pressure strategy in the control system for signaling hydraulic pressure supplied to the one or more actuators in excess of a pressure determined by the brake control pressure strategy and imposing limitation on injection control pressure when such excess pressure is signaled.

6 more elements

A control system for an internal combustion engine that has a fueling system for forcing fuel into engine combustion chambers where the fuel is combusted to power the engine, an exhaust system through which exhaust gases generated by combustion of fuel in the combustion chambers pass from the engine, an engine brake system that is associated with the exhaust system to brake the engine by controlling exhaust flow during engine braking and that comprises one or more hydraulic actuators that is or are actuated during braking of the engine by the engine brake system, and a hydraulic system for supplying hydraulic fluid under pressure both to the fueling system for forcing fuel into the combustion chambers and to the one or more actuators, the control system comprising:

a fuel injection control strategy for closed-loop control of injection control pressure to cause injection control pressure to correspond to an injection control pressure set by the fuel injection control strategy;
and
a brake control pressure strategy for controlling braking of the engine by selectively communicating hydraulic fluid to the one or more actuators, for signaling hydraulic pressure supplied to the one or more actuators in excess of a pressure determined by the brake control pressure strategy, and for imposing limitation on injection control pressure when such excess pressure is signaled.

Dependencies are inferred from the claim text.