Patent · US Expired

Lift system for concrete slabs

US4017115A · kind A · utility

54Cited by
5References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 17, 1975
Grant dateApr 12, 1977
Priority date
Expiry dateDec 17, 1995

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE04G21/185
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A lifting anchor for incorporation into a poured concrete slab. The anchor comprises a steel sleeve having an irregular exterior surface to effect a bond between the sleeve and the concrete of the slab and an interior surface defining a cylindrical opening formed with an annular abutment. During pouring, concrete is excluded from the interior of the sleeve opening by a plastic cap clipped onto the exterior of the bottom end of the sleeve and a plastic plug telescoped into the upper end of the sleeve. After formation of a slab with the anchor in place, the plug is removable to afford access to the interior of the sleeve. A hoisting coupling is engagable with the anchor through means of a cylindrical body sized for entry into the sleeve. The inner end of the body is provided with a pair of lugs which can be extended radially outward to engage the abutment of the sleeve and contracted radially inward to afford removal of the body from the sleeve. The lugs are selectively movable between the extended and retracted positions through means of an actuating rod extending axially of the body. The outer end of the actuator rod has a device for applying tension thereto so as to permit disenga…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.