Gear selection materials, accuracy and parameters

The gear is a wheel like mechanical part that transmits torque by the engagement of teeth. The gear is driven by other toothed mechanical parts (such as another gear, rack, worm) to change the speed and torque, change the direction of motion and change the form of motion. Due to the advantages of high transmission efficiency, accurate transmission ratio and large power range, gear mechanism is widely used in industrial products, and its design and manufacturing level directly affects the quality of industrial products. The teeth of a gear engage each other and drive another gear to rotate to transmit power. If the two gears are separated, the chain, track and belt can also be used to drive the gears on both sides to transmit power.

Pinion: 45 steel, Quenched and tempered, HB1 = 240

Big gear: 45 steel, normalized, HB2 = 190

Modulus: m=2

Number of teeth: Z1 = 24


Gear ratio: u = Z2 / Z1 = 96 / 24 = 4

Accuracy grade: Grade 8 (gb10095-88)

Tooth width coefficient ψ D: ψ d = 0.83 (recommended value: 0.8 ~ 1.4)

Full tooth height: H = (HA + HF) = 4.5mm

Large gear width: in order to ensure full tooth width contact, the small gear is usually larger than the gear width, so: B2 = 40mm