Locking device for coverings for manholes and other ground openings
US5056955A · kind A · utility
17Cited by
13References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 23, 1990 |
| Grant date | Oct 15, 1991 |
| Priority date | — |
| Expiry date | Apr 23, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T292/0907
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A locking device for a covering comprised of a frame and a cover includes arms, which are inserted in depressions or bores formed in the frame and/or cover, whereby they undergo elastic deformation and consequently form a frictional engagement with the cover. The free end each of the arms project beyond an inner flange of the frame and form there a positive connection between the arms and the inner flange. This results in a simple, but effective connection between the cover and the frame, without requiring machining of the arms or depressions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.