| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a transportation device capable of effectively riding over a step using a member used until now and having a caster structure with excellent economic efficiency. <P>SOLUTION: Small diameter casters 1a, 1b and large diameter casters 2a, 2b are provided at corners of four positions of the bottom surface of a body 10 on diagonals. Transportation is performed making the caster 1b side of the body 10 as a front side. Further, the caster 1a is brought into contact with a lower surface F1 at the front side of the step S, and the body 10 is inclined. When the lowermost part of the small caster 1b on a front side is positioned at a higher position than the step S in a floating state, the small caster 1b on the front side does not abut on the step and passes above the step S. The body 10 is forwardly fallen in this state. Then the floating small caster 1b on the front side is landed on an upper surface F2 and the small caster 1a on the rear side is floated. When the body 10 is pushed from the rear side in this state, the body 10 rides over the step S by a relatively small force by the casters 1b, 2a, and 2b contacted with the upper surface F2. <P>COPYRIGHT: (C)2007,JPO&INPIT |
