Design and Fabrication of a Disposable Grasping Mechanism for Fine Grasping Forceps

Abstract

Endoscopy and catheterization are minimally invasive procedures that assist with postoperative recovery. The tools and instruments used in these procedures require complex fabrication and assembly processes because of their numerous small parts. Therefore, the fabrication and assembly of such parts are expensive, and their disposable usage is difficult. Herein, we developed a small-diameter grasping forceps equipped with a monolithic gripping mechanism. When a tensile force is applied to the loading part, bending joints enable the two tips of the grasping mechanism to move toward each other, thereby allowing grasping. The forceps is then returned to the open state by unloading. The tensile force is applied to one point of the loading section. When driving the two joints of the forceps simultaneously, the displacement of each joint is half that of the unilateral drive, which reduces the stress due to deformation. The designed monolithic forceps requires no assembly, so there is no risk of part dismantlement. Although we manufacture the grasping mechanism via metal injection molding, its design specifications and basic structure are not discussed in this work.