Most traditional engines have one intake valve and one exhaust valve per cylinder. This two-valve valve mechanism is relatively simple and has low manufacturing cost. For ordinary engines that do not require high output power, they can obtain relatively good results. Satisfactory engine output power and torque performance. Engines with larger displacement and greater power should adopt multi-valve technology. The simplest multi-valve technology is a three-valve structure, which is a two-valve structure with one intake and one row plus an intake valve.
On January 29, 1886, the German Karl Benz installed the four-stroke single-cylinder fuel engine he developed into a three-wheeled car and obtained the patent. From this day on, the world really had cars. It can be said that the engine created the car. The basic structure of the engine is composed of cylinder 1, piston 2, connecting rod 3, crankshaft 4 and other major parts. Each cylinder has at least two valves, an intake valve (blue) and an exhaust valve (orange).
The valve gear is an integral part of the engine valve train and plays a very important role in engine operation. The working operation of a fuel engine consists of four working processes: air intake, compression, power generation and exhaust. To make the engine run continuously, these four working processes must be repeated and cycled sequentially and regularly.
Two of the working processes, the intake and exhaust processes, require the engine's valvetrain to accurately deliver the combustible mixture (gasoline engines) or fresh air (diesel engines) in accordance with the working sequence of each cylinder, and discharge the burned gas. Exhaust gas. For the other two working processes, the compression and power processes, the cylinder combustion chamber must be isolated from the external intake and exhaust channels to prevent gas from leaking to ensure the normal operation of the engine. The component responsible for the above work is the valve in the valve mechanism. It is like the human respiratory organ, inhaling and exhaling, it is indispensable.
With the development of technology, the speed of automobile engines has become higher and higher. The speed of modern car engines can generally reach more than 5,500 revolutions per minute. It only takes 0.005 seconds to complete the four working processes. The traditional two-valve system is no longer capable of such tasks. Completing the ventilation work in a short period of time limits the improvement of engine performance. The only way to solve this problem is to expand the space for gas entry and exit. In other words, space is traded for time. Multi-valve technology is the best way to solve the problem. It was not until the promotion of multi-valve technology in the 1980s that the overall quality of the engine made a qualitative leap.