Rolling stairway
US5411111A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 25, 1993 |
| Grant date | May 2, 1995 |
| Priority date | — |
| Expiry date | Oct 25, 2013 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE06C1/397
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A rolling platform ladder includes a frame supporting a stairway and a flat work platform area at the top of the stairway. The frame includes a base portion that has a cantilevered front area for preventing tipping over if the platform is overloaded. A main structural support column is placed at the center portion of the platform and extends down at an angle toward the rear of the base. At least a portion of the platform is positioned in front of the column during use. This configuration enables at least a portion of the platform to be positioned over machines, conveyors and over obstructions. A portion of the base extends in front of the frame so that it can extend under objects elevated slightly above a work surface such as an elevated conveyor or machine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.