| 摘要 |
<p>A ball bat comprises an impact portion, a grip portion, and a flexible bending portion situated between the impact portion and the grip portion. The bat is characterized in that it comprises a fiber-reinforced plastic casing of a predetermined thickness. The slits of a predetermined number are constructed in the casing located at the junction area of flexible bending portion and grip portion. The number of fibers incised to form slits is in a predetermined proportion to the total number of fibers contained in the casing located at the junction area, with the ratio being in the range of 5%-95%. The slits serve to obstruct the transmission of shock from the impact portion to the grip portion of the ball bat. Rigidity and elasticity of the impact portion are different from those of grip and flexible bending portions by virtue of an existence of slits disposed in the latter. Rigidity and elasticity of the junction area of flexible bending portion and grip portion can be adjusted by means of slits to an extent that the optimumeffect of swinging is attained. A covering layer made of a polymeric material can be used to encase the area, where slits are constructed, for the dual purposes of protecting the area and of absorbing the residue of shock.</p> |
