Pneumatic Chisel Driver for Precision Bone Cutting

This paper presents a pneumatic chisel drive mechanism for osteotomy. This mechanism consists of a pneumatic cylinder, a piston, and a chisel. The back end of a chisel is inserted in the cylinder and supported by a spring. The piston in the cylinder is accelerated by compressed air supplied from the back end of the cylinder and collides with the chisel at the front end to give the impact for bone cutting. This mechanism allows the surgeon to hold the cylinder with both hands to aim the chisel edge at the desired point and direction without caring about striking the hammer. The stroke of the chisel is mechanically limited to reduce excessive cut. Dynamic characteristics, such as relationship between supply pressure and cutting power, is evaluated by experiments and analyses.