Cause analysis of vibration in gear transmission

The common failure mode of tooth surface is the fatigue pitting, that is, the fatigue wear. After the gear is stressed, the tooth surface will generate contact stress, the contact stress of the tooth surface will be changed. Under the operation of teeth in contact should be repeated, in the tooth surface (or a certain depth) appear small fatigue crack, crack will continue to spread, metal debris from the tooth surface spalling, forming small punctate pits. After the tooth surface pitting, the tooth profile surface is damaged, so that the vibration and noise is increased, so that it can not work properly.

Pitting appeared on the line in the vicinity of the root surface are connected to. This is because the tooth in meshing process, when the tooth in close to the pitch line meshing, relative sliding velocity direction change, oil film is not easy to form. And when the tooth in the section near the line of engagement, and meshing teeth less rubber injection molding machine, the gear is often only one of the tooth contact. Therefore, the contact stress of tooth surface is larger, so the most easily in the section near the line of pitting.

Hardened gear generally not prone to non corrosive pitting propagation, when pitting, when they occur, expansion, and the formation of pitting propagation. For surface hardening and surface carburizing and quenching of steel gear, tooth surface fatigue crack often occurs first in the hardened layer and soft core department junction, the crack extending, the tooth surface will flake, and tooth surface pitting different appearance, the area and the depth of the spalled pit is pitting than high. The tooth surface flaking phenomenon called spalling.

By improving the tooth surface hardness and improve the properties of lubricating oil, the deflection angle of the drive mode and can improve the precision of gear contact to reduce and prevent the occurrence of fatigue pitting.