Reverse rotation engine
AssigneeBombardier Inc.
InventorAlbert D'Amours
Life of this patent
Estimating the term…
Abstract
A reversing internal combustion engine has an ignition system controlled by a microprocessor which samples the magneto voltage output in order to make decisions concerning spark/timing. By suppressing the spark to allow the engine to slow down, and reapplying the spark at a suitable advance, reversal of the engine is effected from forward to reverse or reverse to forward.
Claims30
A method of reversing the direction of rotation of a two-stroke, internal combustion engine provided with a spark ignition system, the engine having a piston that reciprocates in a cylinder and is connected to drive a rotary crankshaft, said method comprising:
- inhibiting said spark ignition system when the engine is operating normally in a forward direction of rotation, whereby the speed of rotation of the engine crankshaft is continuously reduced;
- monitoring said speed of rotation and when it falls below a predetermined level and before it reaches zero, initiating reversal by reactivating said ignition system to momentarily generate an ignition spark at an angle sufficiently in advance of top dead centre that the forces generated in the associated cylinder are high enough to reverse the direction of movement of the piston before it reaches the top dead centre position, whereby the direction of rotation of said crankshaft is reversed;
- and
- immediately thereafter conditioning said ignition system to generate ignition sparks at a timed frequency that is conducive to operation of said engine in said reverse direction.
A system for reversing the direction of rotation of a two-stroke, internal combustion engine provided with a spark ignition system, the engine having a piston that reciprocates in a cylinder and is connected to drive a rotary crankshaft, said system comprising:
- inhibitor means selectively actuable for inhibiting said spark ignition system when the engine is operating normally in a forward direction of rotation, whereby the speed of rotation of the engine crankshaft is continuously reduced;
- detector means for continuously monitoring said speed of rotation;
- microprocessor means operable when the engine speed is below a predetermined level for reactivating said ignition system to momentarily generate an ignition spark at an angle sufficiently in advance of top dead centre that the forces generated in the associated cylinder are high enough to reverse the direction of movement of the piston before it reaches the top dead centre position, whereby the direction of rotation of said crankshaft is reversed;
- and
- ignition control means for conditioning said ignition system to generate ignition sparks at a timed frequency that is conducive to operation of said engine in said reverse direction.
Dependencies are inferred from the claim text.