Basic design of helical gear drive system

In the optimization design of mechanical design, the methods of advance and retreat, golden section method, conjugate gradient method, coordinate rotation method and complex method are often used. Next, a gear system is designed and optimized based on MATLAB.

High speed and heavy load gears are often affected by high acceleration, large impact load, starting, braking and so on. Therefore, in order to ensure the safety and reliability of operation, the safety factor of gear bending strength should be higher than that of contact strength. The main failure forms of gears are: tooth fracture, tooth surface wear, tooth surface gluing, tooth surface pitting, plastic deformation, etc. It can be seen that the design of high-speed and heavy-duty gear must ensure that the gear does not fail during the whole working life. Because there is no effective design method and design data in engineering practice, the gear is designed according to the two criteria of ensuring the bending fatigue strength of tooth root and the contact fatigue strength of tooth surface at present.

Table is the basic parameters of a high speed and heavy load gear transmission system.

Basic parameters of gear

Tooth numberZ1=17,Z2=50 l
Normal modulusmn=6
Normal pressure angle αn=20
Addendum coefficient ha*=1
Top clearance coefficientC*=0.25
Shaft intersection angleΣ=60°