| 摘要 |
PROBLEM TO BE SOLVED: To provide a grating, by which a non-slip at the time when a pedestrian, a bicycle, a wheelchair, a velocipede for a child or the like passes is conducted sufficiently and which is manufactured simply. SOLUTION: A knurl 12 composed of a milling is formed in the cold by sinking a roll having a knurl on the surface of a main member 11 constituting the grating.
|
