| 摘要 |
1,194,489. Railway vehicle folding steps. UNITED AIRCRAFT CORP. 22 July, 1968 [24 July, 1967], No. 34807/68. Heading B7L. A collapsible staircase which occupies either a platform forming position inside a railway vehicle, Fig. 3, or a step-forming position extending outwardly from the vehicle, Fig. 2, comprises treads 12 and 14 and risers 16 and 18 pivoted together at 40 and 28 with the whole pivoted at 22 to the vehicle door sill 58, there being attached on either side of the treads, frame members 26 and 30 with the treads connected by arms 34 such that in the position of Fig. 2 the lower tread 12 is suspended by a parallelogram linkage, and the frame members 26 being connected by linkage 44, 42 to a gear wheel 52 rotated by a chain 54 from a drive motor 46 for moving the staircase between its two positions. Microswitches 68 and 72 limit the movement of the staircase by cutting out the motor when contacted by link 42. The platform in the Fig. 3 position is formed by tread 12 and riser 16 and a support by frames 32 attached to frame members 30. |
