Covering for a ground opening
US5017039A · kind A · utility
18Cited by
9References
6Claims
0Family size
Inventors
Key dates
| Filing date | Jul 5, 1989 |
| Grant date | May 21, 1991 |
| Priority date | — |
| Expiry date | Jul 5, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02A30/60
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A covering for a ground opening includes a frame in which a cover can be inserted. The frame has a recess for receiving a retaining web shaped onto the edge of the cover. A niche with a sloping bearing surface is formed in the frame at a distance from the recess. The cover has a cam. When the cover is in the closed position, a supporting wall provided on the cam formed on the cover edge rests on a bearing surface of the frame, so that, on closing the cover, the later is moved in the direction of the recess and assumes a locked position. Thus, the cover is held in a clearance-free manner in the frame.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.