Frame for forming coverings on ground openings
US4904120A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 1988 |
| Grant date | Feb 27, 1990 |
| Priority date | — |
| Expiry date | Sep 28, 2008 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02D29/14
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A frame for forming coverings for ground openings and method of assembling such frame are disclosed. Frame parts for assembling the frame are provided at their ends with connecting lugs, which are arranged at different levels. On fitting the frame, the two frame parts are juxtaposed, their connecting lugs are arranged in spaced superimposed manner and are interconnected by screw couplings. For positively interconnecting the frame parts, the frame is turned upside down, and a liquid, pasty or granular filling material is filled into a bore on the underside of the upper connecting lug. The filling material also flows into the bore of the screw coupling, which is covered by a washer. Following the solidification of the filling material, the frame can either be transported in this state or in a disassembled state and can be then reassembled in the same way.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.