A magneto is a simple and reliable device that generates electricity for ignition in small engines, like those found in lawnmowers, motorcycles, and some cars.
How It Works:
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Rotating Magnet: The heart of a magneto is a permanent magnet attached to the engine's crankshaft. As the engine runs, the magnet spins.
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Coil: A coil of wire, called the stator, is positioned near the rotating magnet. This coil is stationary.
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Electromagnetic Induction: As the magnet spins, the changing magnetic field cuts through the coil, inducing an electric current. This current is the spark that ignites the fuel-air mixture in the engine's combustion chamber.
Key Components:
- Stator: The stationary coil that receives the magnetic field.
- Rotor: The rotating magnet attached to the crankshaft.
- Breaker Points: (In older magneto systems) These contacts open and close the circuit at the right time to create a spark.
- Capacitor: Stores electrical energy to provide a stronger spark.
Advantages of Magnetos:
- Simplicity: They have fewer moving parts than other ignition systems, making them more reliable.
- Self-Contained: Magnetos don't require external power sources like batteries.
- Robustness: They are built to withstand harsh environments and vibrations.
Example:
Imagine a bicycle wheel with a magnet attached to its spoke. As the wheel spins, the magnet passes by a stationary coil. This movement creates a current in the coil, just like a magneto in an engine.
