Internal combustion engine having deceleration fuel shut off and camshaft controlled charge trapping
AssigneeFord Global Technologies, LLC
InventorsStephen George Russ, William Francis Stockhausen
Life of this patent
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Abstract
A reciprocating internal combustion engine using poppet valves, valve timing control and fuel injection, cuts off fuel during engine deceleration and controls valve timing such that charge is trapped in the engine cylinders while the fuel is shut off. As such, catalytic after treatment devices are neither cooled nor saturated with oxygen and engine fuel economy is improved.
Claims6
A method for operating a poppet valve equipped, multicylinder internal combustion engine having a catalytic aftertreatment device, so as to trap charge in the cylinders during a DFSO operating mode, so as to avoid cooling and oxygen loading of the catalyst during DFSO, comprising the steps of:
- sensing deceleration of the engine;
- adjusting the timing of the poppet valve opening and closing events by retarding the timing of the intake and exhaust valves equally such that no net flow of gases to and from the cylinders occurs;
- and
- shutting off fuel supplied to the cylinders of the engine when a suitable air charge is no longer available within the cylinders.
Dependencies are inferred from the claim text.