Adjustable roof scaffold jack
作者： Maurice Shaffstall
DOI:
关键词: Base (geometry) 、 Engineering 、 Scaffold 、 Roof 、 Structural engineering
摘要: An adjustable roof scaffold jack means for mounting on a pitched that includes adjustment coupled to support member adapted be leveled the horizontal receiving platform workman use in working vertical or angular surface adjacent said roof. The include base and hinged with extending therebetween. when used additional forming platforms conventional which are tied together present safe area workmen stand on.
lens.org 参考文章(3)
Henderson G Leonard, Demountable scaffolding for side mounting on columns ,(1961)
George D Mackenzie, Sr Liday Elury Hamilton, Safety roof bracket ,(1951)
Rene Ralph, Variable pitch roof bracket ,(1963)