Patent · US Expired

Method of manufacturing box ladders

US5317798A · kind A · utility

9Cited by
3References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 10, 1992
Grant dateJun 7, 1994
Priority date
Expiry dateMar 10, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49876
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A method of manufacturing box ladders having a pair of side rails and rungs wherein each of the side rails are assembled from a pair of section members having holes pre-formed prior to assembly of the side rail. The method provides reduced deformation in the manufacture of box ladders having cylindrical rungs and provides for the manufacture of box ladders having non-cylindrical shaped rungs.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.