Plastic gear is mainly used for precision and intensity is not too high gearing. Gear has used plastic, nylon, polycarbonate, polyacetal, polysulfone and the like. In order to adapt to the injection molding process, the gear, the gear rim, spokes and hub should have a certain thickness.
To minimize the effects of stress concentration at sharp corners and gear in forming internal stress, we should try to avoid sudden changes in cross-section, as far as possible and increase the radius of the fillet arc transition. To avoid internal stress with the axis of the hole as far as possible without using the assembly interference fit, while the use of transition fit.
For a thin gear, because of uneven thickness can cause skew, it will skew gear. Because of the different plastic shrinkage is different, so the general shrinkage of the same plastic bevel gear teeth with each other together. |
