Why can the timing belt drive replace the gear drive?

Synchronous pulleys are suitable for transmission over long distances, but the accuracy and load carrying capacity are not as high as gear transmission. Under higher precision requirements, larger loads and higher speeds, the gear transmission cannot be replaced. If the working conditions are very low, the working principle of the synchronous belt is the same as that of the gear. It is the meshing transmission, but there is a difference. The accuracy and load carrying capacity of the synchronous belt transmission are not as high as the gear transmission. However, it can be driven at a long distance. The gear transmission needs to have a large structure. The belt drive can meet the distance requirement, but the bearing requirements cannot be met. With the chain drive, the transmission ratio accuracy is worse than the synchronous belt. Therefore, when the load is moderate, the timing belt is suitable when the distance is long.

The torque of the gear drive is the highest, so the high-intensity drive selects the gear. However, the gear transmission will change the steering, and the distance from active to driven is limited. The chain drive is suitable for a long distance plus constant steering, but consider tensioning!

The chain drive is not very useful in high-speed transmission (also used in engines, and its additional mechanism is complicated), and the timing belt and gear are suitable for high speed. However, the gear has high requirements for smoothness, the timing belt is not required, and the noise is small. Because the timing belt is rubber, there are also drawbacks in non-uniform transmission, high torque may be broken, etc...

In short, each drive has its own advantages and disadvantages! At the same time, the belt drive is a soft connection, with buffering, low noise and so on.

Gears require higher machining accuracy and relatively higher cost. It is more suitable for clearance when assembling. Generally, the equal modulus is used to make the same pair of teeth engage each time. It takes a period of time to maintain and add lubrication.