Lift-assisted manhole cover
US7341398B2 · kind B2 · utility
17Cited by
19References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 24, 2006 |
| Grant date | Mar 11, 2008 |
| Priority date | — |
| Expiry date | May 24, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7021
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A lift-assisted manhole cover assembly with a flush surface and external pivot shaft. The cover includes a mounting tab that extends beyond the general periphery of the cover. The mounting tab may be connected to a shaft that is threadedly engaged with the frame. A spring may be mounted between the frame and the mounting tab, for example, in a sleeve, to provide a mechanical assist in lifting the cover. The sleeve may be disposed outside the manhole opening where it does not block access to the manhole opening.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.