The crankshaft is a shaft that connects all the pistons in a diesel engine of a diesel locomotive. The pistons act on the crankshaft via connecting-rods; therefore transferring the power to the rest of the drive-line (either an electric generator or gearboxes, drive-shafts, differentials etc.).
The crankshaft has 'throws' (offset sections) that, due to their offset, throw the pistons at different times. In an in-line four-cylinder engine the two outside pistons work in harmony, but opposite to the two inside pistons that work in harmony. In other words when the two outside pistons are at the top of their cylinders (cylinder head), the two inside pistons are at the base of their cylinders.
On four-stroke engines, attached at the end of the crankshaft is the flywheel. This smooths the transition between piston 'beats' (cylinder firing).
- Encyclopædia: Britannica Deluxe Edition. 2010.