poppetventil

A poppet valve is a type of valve that opens and closes the flow of a fluid by means of a disc-shaped or plug-shaped component, the poppet, which is moved away from or into a circular hole, the valve seat. The poppet is typically attached to a stem that moves it up and down. In its closed position, the poppet is pressed tightly against the valve seat, forming a seal that prevents flow. When the stem is lifted, the poppet moves away from the seat, allowing fluid to pass through the opening.

Poppet valves are commonly used in internal combustion engines, where they control the intake and exhaust of fuel-air mixture and combustion gases into and out of the cylinders. In this application, the poppet valve is actuated by a camshaft, which is driven by the engine's crankshaft. The shape of the poppet and the valve seat are critical for achieving a good seal and efficient flow. They are often made of specialized alloys to withstand high temperatures and pressures.

Beyond automotive engines, poppet valves are found in a wide range of applications, including pneumatic and hydraulic systems, steam engines, and various types of pumps and compressors. Their design allows for relatively simple construction and reliable operation, making them a versatile choice for fluid control. The sealing effectiveness can be influenced by factors such as the fit between the poppet and seat, the spring force holding the valve closed, and the pressure differential across the valve.