Device capable of extending a foot end of a ladder
US8297406B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 23, 2011 |
| Grant date | Oct 30, 2012 |
| Priority date | — |
| Expiry date | Jun 29, 2031 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE06C7/423
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A device capable of extending a foot end of a ladder includes a box tube section with an elongated hole, a long engaging plate with an elongated hole and a plurality of inserting teeth, a short engaging plate with a central fixing hole, two pairs of engaging slots and an engaging nut, and a knob head bolt. The knob head bolt passes through the elongated holes, and the central fixing hole to be tightened to the engaging bolt via a rail of the ladder. The long and short engaging plates are disposed in the box tube section to face to each other. The knob head bolt is loosened or tightened to cause two pairs of the inserting teeth disengaging or inserting into the engaging slots for the box tube section being operated to extend a distance outward the rail stably and safely.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.