| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a crank arm for bicycle superior in strength, and suitable for enhancing production efficiency. <P>SOLUTION: The crank arms 3 and 4 for bicycle include boss parts 31 and 41 having a fitting part to be fitted to a crankshaft 2, and arm parts 32 and 42 longitudinally extending from the base end connected to the boss parts 31 and 41 to the tip. The arm parts 32 and 42 have hollow parts 321 (421) along the longitudinal direction, and the hollow parts 321 and 421 are open on the base end side of the arm parts 32 and 42. <P>COPYRIGHT: (C)2012,JPO&INPIT |
