Composite Wheel Hub Geometry to Prevent Shrinkage Cracks

The root of the drive teeth is designed with a rounded profile instead of sharp edges. The curvature radius at the tooth root is specifically optimized to eliminate stress concentration points while maintaining adequate torque transmission capability. This rounded geometry prevents the formation of stress notches that would otherwise lead to crack initiation during the cooling and shrinkage of the plastic rim body.

The grooves are designed with specifically optimized dimensional parameters including depth, width, and most importantly, rounded edges with controlled curvature radii. These parameter optimizations ensure that the plastic material distributes evenly during cooling and shrinkage, preventing differential shrinkage that would cause play or noise. The groove dimensions are tailored to maintain adequate engagement for axial force transmission while accommodating uniform shrinkage behavior.

All edges and corners on the hub body surface that contact or engage with the plastic rim body are designed with rounded profiles instead of sharp edges. The curvature radii are specifically optimized to eliminate stress concentration while remaining compatible with standard manufacturing processes. This approach maintains ease of manufacture through conventional molding techniques while dramatically improving resistance to crack formation during operational loading.