crankshaft

Everyday

A crankshaft is a long metal rod in an engine that turns the up-and-down movement of the pistons into turning (spinning) movement that drives the wheels. tree →

In the lessons

In science and design technology, the crankshaft is an example of a mechanism that changes one kind of motion into another, like the pedals and crank of a bicycle. Cars, motorbikes, boats and old steam engines use crankshafts.

Examples

• The pistons push the crankshaft round. tree →
• A broken crankshaft means the engine cannot work. tree →
• A bicycle's pedals turn a crank, a little like a crankshaft. tree →
• The mechanic showed us the crankshaft inside the old engine. tree →
• In D&T we built a model with a crankshaft that made a toy bird flap. tree →
• Steam engines used a crankshaft to turn their wheels. tree →

Note

Countable. A «crank» is a handle or arm bent at a right angle that you turn; a «shaft» is a long rod. Crank also has an informal meaning: a strange person with odd ideas.