Background: The perineum area that interacts with the saddle is vulnerable; compressing
neurovascular tissues has been asserted as the link to pathologies. Existing saddle designs are
mainly based on the hole blocks, which are composed of two materials. These composite combined
structures increase manufacturing difficulty.
Objective: The injection molding technology is suitable for mass production. We proposed a saddle
design to meet the ergonomic requirements of cyclists. Saddle frames present a continuous curvature
geometry to ensure improved injection modeling.
Methods: Static numerical calculations and measurements were employed for vertical load evaluations
with different stiffness regions acquired using perforated chain patterns. Two-step plastic injection
molding was utilized with proper bonding and processing compatibility. In prototyping, the
first and second shots are PC and TPE, respectively.
Results: The frame sustains vertical loadings from bending and provides adequate stiffness and
proper flexibility. The computer-aided design mold increases the contact area, and annular grooves
increase the adhesion between two materials. The outer frame exhibits high rigidity; the middle area
exhibits flexibility and high deformation.
Conclusion: This question is widely noticed and various answers have been proposed. By investigating
the patent database and searching journal papers on saddle designs, the authors confirmed
the novelty of the proposed structure.