Means for curving side by side concrete curb sections
US3941545A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 1974 |
| Grant date | Mar 2, 1976 |
| Priority date | — |
| Expiry date | Jan 21, 1994 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB28B11/003
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Apparatus has heretofore been provided for the automatic pre-casting of concrete curbing. The pre-cast curbing, in a zero slump state, emerges in spaced parallel pairs from this apparatus. The present invention provides for an initial bending of both curbs in opposite directions by the insertion of a tool between them. Then, a final bending is performed to the desired curvature. The apparatus comprises an elongated prebending member having an inverted triangular section and convex sides from end to end. The maximum curvature is at the top, and it gradually tapers away toward the bottom so that the amount of curvature to the curbs is controlled by the depth of penetration of the member between the curbs. A second, generally inverted U-shaped member is formed with the required bend. This member is forced over one of the curbs to complete the bend. It is then lifted, turned 180.degree., and forced over the companion curb to complete its bend. The entire process must be performed within the first ten minutes of leaving the pre-casting apparatus, and preferably within the first three minutes, to ensure sufficient pliability in the curb before its setting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.