Car Body Frame Member Continuous Reinforcing Bead

The patent applies local quality by forming reinforcing beads specifically at the bent portion where stress concentration occurs during collisions. Instead of uniformly increasing thickness throughout the extension member, the bead structure provides localized reinforcement exactly where needed, enhancing cross-sectional proof stress while minimizing additional weight.

The reinforcing bead introduces a curved, three-dimensional structure on the surface of the extension member. This curvature creates a geometric reinforcement that increases moment of inertia and cross-sectional proof stress without requiring additional material thickness, effectively using shape modification to improve strength.

The patent implements continuity of useful action by forming the reinforcing bead continuously from the straight portion through the bent portion to the extension member. This continuous bead structure ensures uninterrupted stress distribution and flexural rigidity enhancement along the entire length, preventing stress concentration at bead discontinuities while maintaining collision resistance.

The patent applies parameter changes by modifying the bead formation parameters specifically for the bent portion region. The bead continues from the straight portion but with adjusted geometry and positioning to optimize reinforcement at the critical bent area, allowing flexible control of reinforcement characteristics through parameter adjustment rather than structural redesign.