| 摘要 |
<p>A support beam or column arrangement comprises a plurality of sections 2A,2B???2X which are connectable end-to-end by a connecting system 13 which is totally internally cooperable with the sections upon relative expansion of members 26,27 by tunbuckles 36A,37A. The sections are provided with flanges (22,23,24,25 Fig. 4) which are used to provide guide channels (46 Fig. 4) for wheels (45 Fig. 4) provided on user foot support plate assemblies or units 11 which are displaceable lengthwise of the sections. A control system comprising a rack and paw (48,53 Fig. 5) or toothed wheel and rack and braking system (75,87,80 Fig. 9) is used to prevent or allow lengthwise movement of the foot support plates by the user so that by alternately moving each plate the user can climb or descend the beam or column 2. <IMAGE></p> |
