Spiral staircase
US4118908A · kind A · utility
3Cited by
4References
6Claims
0Family size
Inventor
Key dates
| Filing date | Dec 6, 1976 |
| Grant date | Oct 10, 1978 |
| Priority date | — |
| Expiry date | Dec 6, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T403/4602
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A spiral staircase having at least one straight section and at least one curved section wherein the steps are supported at one end thereof on a wall and at the other end are suspended from a handrail and wherein the handrail is formed from straight sections having a substantially uniform height above the steps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.