| 摘要 |
Two or more parts (7',4') forming the platform are longitudinally movable relative to each other. The one inner part (4') comprises two parallel lower rails (4a',4b') joined to each other by a floor plate and the rails hold the railing provided along the floor. The other lower part (7') comprises two parallel lower rails (7a',7b') which are also joined by a floor plate (7c'), with the rails retaining the corresp. railing. The inner and outer parts of the structure comprise non-pliable units displaceable in relation to each other via rollers, with which they work in conjunction. |
