Removable insert for forming holes in concrete and the like
US4365780A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 23, 1981 |
| Grant date | Dec 28, 1982 |
| Priority date | — |
| Expiry date | Mar 23, 2001 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE04G15/063
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The present device is especially useful for positioning on forms prior to the pouring of concrete for removal therefrom to create holes in the concrete to receive inserts therein such as in making holes in concrete for steps to be used in a manhole. A tapered steel shaft of any selected length has a collar fixed near one end thereof with an elongated handle passing transversely therethrough. The collar has slanted cam edges on each end providing a cam surface which is approximately 12.degree. from a line perpendicular to the axis. A second collar identical to the first is welded to a form, such as a steel concrete form used in pouring concrete for manholes. The second collar also has slanted cam edges providing a cam surface corresponding to the slanted cam edges on the first collar and there is a hole passing through the steel pin and through the second collar to receive a removable latch pin therein. The steel pin is inserted through the second collar and fixed in place until after the concrete is poured and has cured sufficiently at which time the latch pin is disengaged and the handle is turned to rotate a cam edge of the first collar against a cam edge of the second collar the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.