Viertaktig

"Viertaktig" is a German term that translates to "four-stroke" in English. It refers to an internal combustion engine that completes a power cycle in four distinct strokes: intake, compression, combustion, and exhaust. This type of engine is commonly used in automobiles and is known for its efficiency and power output.

The four-stroke cycle begins with the intake stroke, where the intake valve opens and the piston moves downward, drawing a mixture of air and fuel into the cylinder. The compression stroke follows, where both valves are closed, and the piston moves upward, compressing the air-fuel mixture. The combustion stroke occurs next, where the spark plug ignites the compressed mixture, causing a rapid expansion of gases and pushing the piston downward. Finally, the exhaust stroke begins, where the exhaust valve opens, and the piston moves upward, expelling the burned gases from the cylinder.

Viertaktig engines are favored for their smooth operation, high power-to-weight ratio, and relatively low emissions compared to other types of engines. They are widely used in various applications, including cars, motorcycles, and generators. However, they are generally more complex and heavier than two-stroke engines, which complete the power cycle in two strokes.