| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the separation of a specific portion from a remaining portion to be hindered by providing a locking mechanism preventing the remaining portion from rotating when the specific portion is separated and permitting wheels to rotate when the specific portion is mounted even at a specific separation position and any rotation position other than that. <P>SOLUTION: The safety mechanism includes: a wheel separation mechanism 7 permitting circular wheels 5 to be separated into fan-shaped specific portions 5a including parts of the outside peripheries of the wheels and remaining portions 5b except the specific portions in a specific separation position F to form an open space K necessary for getting on and off; and the locking mechanism 9 preventing the remaining portion from rotating when the specific portions are separated and permitting the wheels to rotate when the specific portions are mounted. <P>COPYRIGHT: (C)2012,JPO&INPIT |
