| 摘要 |
<p>The invention provides a cylinder-shaped hollow shaft capable of realizing light weight and high intensity, comprises the hollow shaft and a cylinder magnetic roller of permanent magnet attached on the outer circumference surface of the hollow shaft, and comprises a sleeve pipe and a developing roller of the magnetic roller arranged in the sleeve pipe. The hollow shaft is formed in a cylinder and strip shape. Three concave portions extending in straight lines in an axis direction are arranged on the outer circumference of the hollow shaft, and are arranged at equal intervals in the circumference direction. Each concave portion has same shape, and the concave surface is formed in an arc shape.</p> |
