軟式野球用バットの反発性に関する研究

抄録

In this research, the collisional properties of a bat and ball was investigated experimentally for the purpose of hitting performance improvement of the rubber-ball baseball bat which is one of the popular sports in Japan. First, three marketed bats for the rubber-ball baseball of the typical materials were chosen and investigated the coefficient of restitution by the ball collision test based upon ASTM F 2219, as a result, the tendency that coefficient of restitution was increased in the collision position of the ball was near a grip with all bats. Next, it was assumed the influence of the diameter of the collision position as a factor that coefficient of restitution increased on the grip side of the bat and the ball collision test by the cylinder rigid iron of various diameters was examined. As a result, it was confirmed that coefficient of the restitution increases under the condition of small diameter. A similar result was shown for the numerical simulation by FEM and some useful knowledge was obtained for the design of high-performance rubber-ball baseball bat.