Planet Tooth Edge Geometry for Rolling Contact Gear Stress

The patent applies local quality by differentiating the geometry of edge teeth from intermediate teeth. The first edge teeth are formed with reduced dimensions (smaller tooth thickness and/or height) compared to the standard tooth contour, while intermediate teeth maintain the full tooth contour. This local modification reduces stress concentration at the edges where breaking off typically occurs, while preserving adequate load-bearing capacity through the intermediate teeth.

The ring of first teeth is segmented into three functional groups: two first edge teeth at the ends with reduced geometry, and multiple first intermediate teeth in between with full geometry. This segmentation allows different parts of the tooth ring to serve different functions - the edge teeth provide stress relief and guidance, while the intermediate teeth provide the primary load-bearing contact area.

The patent modifies only the local geometry of the first edge teeth while maintaining the standard tooth contour for first intermediate teeth. The edge teeth have reduced tooth thickness and/or height, creating a gradual transition in contact area that reduces stress concentration without significantly compromising the overall force transfer efficiency provided by the intermediate teeth.

The patent applies partial action by forming the first edge teeth with reduced dimensions compared to the full tooth contour. This partial formation is sufficient to reduce edge stress and prevent breaking off, while the first intermediate teeth provide adequate rolling contact area for efficient force transfer. The edge teeth serve primarily as stress-relief elements rather than full load-bearing elements.