| 摘要 |
<p>PURPOSE:To obtain a bat having an excellent strength against impulsive compression load and an excellent swing balance and further increasing flying distance of a stroken ball, by providing a pipe for composite backing up made of a foamed core material in the inner layer and a reinforced plastics in the outer layer. CONSTITUTION:This bat consists of a foamed core material 1 similar to the whole shape, which is formed in the full length of the inside from the grip to the hitting end, and a back up pipe 2 having the same outer diameter as the foamed core material and unified at the hitting part of the core material. And it consists of a fiber-reinforced plastics layer 3 with longitudinally arranged fibers in order to chiefly secure the bending strength and a fiber-reinforced plastics layer 4 with circumferentially arranged fibers in order to chiefly resist impulsive compression loads. Aluminum alloy traditionally used for a bat is preferable in the strength and weight for the back up pipe. And pipes made or reinforced plastics arranged peripherally with light and highly rigid reinforced fibers are also preferable.</p> |
