Ladder
US8668049B2 · kind B2 · utility
22Cited by
22References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 29, 2008 |
| Grant date | Mar 11, 2014 |
| Priority date | — |
| Expiry date | Nov 23, 2029 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE06C1/12
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A ladder comprises two stiles and at least a step unit mounted between the two stiles. The step unit includes a hollow step, an inner sleeve and an outer sleeve. The inner sleeve is fit into the hollow step, at an end of which a position restriction portion is located to prevent the inner sleeve from moving out, and the outer sleeve is adapted to surround the end of the hollow step. Besides, a fastener is set, the fastening end of which is passed through the stile, the outer sleeve and fastened in the inner sleeve. The present technique solution has a high supporting strength and a high shear resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.