Robust Optimal Design of a Six-Bar Linkage-Based Finger Clamping Unit for High Durability

Abstract

A finger clamping unit (FCU) is a clamp for fixing a thin panel through a toggle mechanism in which the torque input is amplified. Previous studies optimized the clamping range (range of thickness of a panel that can be clamped) using a compliant link. Thereby, panels of various thicknesses could be clamped. However, a problem occurred in the durability because of the optimization to increase only the clamping range. The most vulnerable part, the compliant link, was damaged. In this study, durability is improved by replacing the linear slide joint (the mechanical element of the FCU) with a curved slide joint from another study. A static analysis of the new FCU is conducted. In addition, optimization is performed to reduce the force applied to the compliant link using the Taguchi method in a simulated environment. The result is expressed as a three-dimensional plot representing the behavior of the FCU. As a result of optimization, durability has increased significantly. furthermore, the clamping range is also increased slightly, and the overall size of the FCU is decreased. In addition, the increase in durability was greater when subjected to a large force than when subjected to a small force. When the penal thickness is 2mm, the force applied to the compliant link is decreased by 15.85%.