1, engage the pinyin niè hé, (move) bite the upper and lower teeth; Two things are connected like upper and lower teeth and bite tightly: two gears mesh tightly.

2. Meshing refers to a transmission relationship between two mechanical parts, which is called meshing transmission. Gear transmission is the most typical meshing transmission and the most widely used transmission form. According to the different transmission principles, there are spur gear meshing transmission and helical gear meshing transmission.