| 摘要 |
PURPOSE:To reduce a housing in weight while scarcely decreasing the rigidity of the column of the housing by providing a hollow part to the column. CONSTITUTION:The housing 6 has the circularly sectioned hollow part 10 to the overall axial length of the column 9. The structure using the housing 6 constituted as mentioned above positions a head and writes and reads information, but the hollow part 10 is provided to the column 9, so that housing 6 is reduced in weight while scarcely decreasing the rigidity. |
