Hoisting coupling for concrete slabs
US4325575A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1977 |
| Grant date | Apr 20, 1982 |
| Priority date | — |
| Expiry date | Mar 28, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66C1/666
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A remotely releasable hoisting coupling for engagement with an anchor cast in place within a concrete slab. The anchor provides a passage opening through the surface of the slab and an annular abutment shoulder spaced beneath said surface. The coupling comprises a body insertable into the anchor, a pair of lugs supported in the body at diametrically opposed positions for rocking movement about a diametric axis extending normal to the body, and means to selectively move the lugs between a protruding condition engaged with the abutment shoulder and a retracted condition disengaged from the shoulder. The means to selectively move the lugs comprises a rod axially moveable within the body and having cam surfaces directly engagable with the lugs to force the lugs to the protruding condition and holding surfaces to maintain the lugs in the protruding condition, without loading the cam surfaces. A lifting bail is carried by the body for pivotal movement about an axis extending parallel to the diametric axis of the lugs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.