What are the different forms of failure in open and closed gear drives? What are the design criteria?
Then, the bending fatigue strength of the gear teeth is checked. When using the hardened (tooth surface hardness more than 350HBS), generally should first press the gear bending fatigue strength condition, determine the modulus gear and the main geometric parameters, and then check the tooth surface contact fatigue strength
The main failure modes of the closed drive are the pitting on the tooth surface and the bending fatigue fracture of the gear. When using a soft tooth surface (tooth surface hardness is less than or equal to 350HBS), the tooth surface contact fatigue strength is relatively low. Therefore, the diameter of the gear circle and its main geometric parameters (such as the center distance and the width of teeth) should be calculated first according to the fatigue strength condition of the tooth surface,
The main failure modes of open drive open drive are the abrasive wear on the tooth surface and the bending fatigue fracture of the gear tooth. At present, there is no perfect calculation method for the abrasive wear of tooth surface, so the bending fatigue strength is usually calculated, and the effect of abrasive wear is considered by increasing the modulus.
