There are three main transmission modes of camshafts, namely gear transmission, chain transmission and toothed belt transmission.
Gear transmission: This method is mainly used in the lower and middle valve mechanism of the camshaft. Usually, only a pair of timing gears are required for transmission from crankshaft to camshaft, but intermediate gears can also be added if necessary. Timing gears often use helical teeth, which can reduce noise and ensure smooth meshing. The timing accuracy of the gear transmission is high, but for the overhead camshaft type valve mechanism, due to the spatial layout, the chain or toothed belt drive must be used.
Chain drive: Chain drive is mainly used in high-power engines, such as mid-to-high-end cars and trucks. The chain drive can ensure the accuracy of the valve timing, and the work is reliable and durable. But chain drive also has some disadvantages, such as the timing changes after the chain is worn, and it needs to be checked and replaced regularly.
Toothed belt drive: Toothed belt drive is mainly used in ordinary passenger cars. Toothed belts are generally made of neoprene with fiberglass and nylon fabric sandwiched in between for added strength. The toothed belt has a long service life and can reach more than 100,000 kilometers. Moreover, the toothed belt transmission noise is small and the transmission is smooth, but it also needs to be checked and replaced regularly.
In general, the choice of transmission mode of camshaft mainly depends on the type of engine and the environment in which it is used. Different transmission methods have their own advantages and disadvantages, which need to be selected according to the specific situation.
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