Design, Analysis, and Experimental Evaluation of a New Expansion Screw Using Compliant Mechanisms

This article presents a design solution for a new expansion screw based on compliant mechanisms. The new expansion screw applies distributed compliant mechanisms, rhombus amplification mechanisms, and right circular flexure hinges to it. The distributed compliant mechanism realizes the contraction, the rhombus amplification mechanism realizes its expansion and fixation, and the right circular flexure hinges are used to reduce friction. The forces analysis of the new expansion screw when it works is used to calculate its maximum load-bearing capacity. A series of simulations and experiments are carried out to demonstrate the practicability and efficiency of the new expansion screw. In experiments, the new expansion screws using acrylonitrile butadiene styrene (ABS) and nylon plastic are fabricated, respectively, and the expansion screws using nylon plastic already available on the market are set as a comparison. The experimental results indicate that the structure of the new expansion screws is better than the existing expansion screws on the market, and the corresponding overall bearing capacity is more than double than the expansion screw already available on the market. The new expansion screw realizes a significant increase in its bearing capacity and shows a strong application prospect.