Apparatus for forming inverts and manhole assemblies and the like utilizing adjustable invert forming members joined with an intermediate flexible portion
US4941643A · kind A · utility
25Cited by
11References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 26, 1989 |
| Grant date | Jul 17, 1990 |
| Priority date | — |
| Expiry date | Jan 26, 2009 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE03F5/02
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Apparatus for forming inverts in a manhole base comprising at least one adjustably positionable channel-forming member for forming an invert which communicates between associated sidewall openings of a manhole base. Flexible members join the ends of the invert form. The adjustability of the channel-forming assembly extends over a range of angles which are both greater than and less than 180 degrees.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.