| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a tread for prefabricated stairs not only having light weight capable of easily carrying out prefabricated work to an open string even by a single person but also having excellence in decoration effect and durable strength. <P>SOLUTION: Right and left nuts (21), (23) each in pair, four in total are integrally embedded in a tread board (11) extrusion molded in a hollow flat board mode from an aluminum alloy to screw and fasten tension bolts (25) and (26) between both right and left nuts (21) and (23) in a cross state, a pair of right and left side cover plates (30) stuck with elastic sheet packings (39) are mounted and fixed to the tread board (11) from the lateral outside with tapping screws (31), (32) and (33) in a cross sectional state, and the tread board (11) is so positioned that it is mounted and fixed to a steel plate open string (47) with construction bolts (50) and (51) screwed and fastened to the nuts (21) and (23) from the lateral outside of the steel plate open string (47). <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
