Gears transmit power through the meshing between teeth. When two gears mesh, the rotating motion of one gear is transferred to the other gear. In the process of transmitting power, parameters such as the number of teeth and modulus of the gear will affect the transmitted speed and torque. Specifically, when a drive gear rotates, its teeth bite with those on the driven gear, creating a relative roll that transfers energy to the driven gear. According to the design of the gear, the ratio of the number of teeth between the drive gear and the driven gear, that is, the gear ratio, determines the speed and torque transmitted to the driven gear. Generally speaking, if the number of teeth of the driving gear is greater than the number of teeth of the driven gear, the speed can be reduced but the torque can be increased; Conversely, if the number of teeth of the drive gear is less than the number of teeth of the driven gear, the speed can be increased but the torque can be reduced. The advantages of gear transmission include high transmission efficiency, high precision, large transmission capacity, etc., so it is widely used in many mechanical devices, such as automotive transmission systems, industrial machinery, machine tools, etc.
