What is the principle of a governor?
2 Answers
The principle of a governor is to automatically adjust the fuel supply of the injection pump based on changes in diesel engine load, ensuring the diesel engine operates at a stable speed. The functions and classifications of a governor are as follows: Functions of a governor: A governor changes the load of the diesel engine while maintaining a constant speed. If the speed remains unchanged, adjusting the fuel quantity can alter the diesel engine's load. Conversely, if the diesel engine's load remains constant, changing the fuel quantity can adjust its speed. Main classifications of governors: Based on their working principles, governors can be divided into mechanical, pneumatic, hydraulic, mechanical-pneumatic hybrid, mechanical-hydraulic hybrid, and electronic types, among others. Currently, the most widely used is the mechanical governor, which features a simple structure, reliable operation, and excellent performance.
Having driven for so many years, I'm quite familiar with the old mechanical governor. Simply put, it relies on the engine spinning a few metal weights—the faster they spin, the farther they fling outward, pushing the fuel linkage to reduce throttle. When the throttle is eased, the engine slows down; as the RPM drops, the springs pull the weights back in, opening the throttle wider. This mechanical setup keeps diesel engines running steadily at the set speed, avoiding both black smoke bursts and overspeeding cylinder damage. Thinking back, in the era without wires, it was all these little mechanisms maintaining power balance. When repairing, seeing worn-out flyweights made it clear why the RPM fluctuated up and down.
