| 摘要 |
PROBLEM TO BE SOLVED: To reduce weight of a clutch drum while preventing increase of mechanical loss of the clutch drum. SOLUTION: This clutch drum 15 houses plural clutch plates 17 and includes a cylindrical part 23 and plural teeth 25 arranged on an inner periphery side of the cylindrical part 23 in a line in a circumference direction and extended in a shaft direction. The plural teeth 25 includes a tooth top part 29 and a tooth surface 31 on both side in a rotation direction and the cylindrical part 23 has tooth bottom surfaces 35 formed on an inner periphery surface side between plural teeth 25 in a rotation direction. Outer periphery recess parts 37 are formed on parts corresponding to the plural teeth 25 on an outer periphery surface of the cylindrical part 23 and inner periphery recess parts are formed on an inner periphery surface of the plural teeth 25. |
