Coil disk anchor

Abstract

An anchor for lifting, connecting to, and/or bracing a precast concrete structure, the anchor including a shaft defining a first end, a second end, and a longitudinal axis; and a circular plate coupled to the second end of the shaft, the circular plate oriented perpendicular to the longitudinal axis, wherein the shaft defines an opening extending from the first end of the shaft towards the second end of the shaft in a direction generally parallel with the longitudinal axis, the opening having a sidewall with a helical thread.

What is claimed is: 
     
         1 . An anchor for lifting precast concrete, the anchor comprising:
 a shaft defining a first end, a second end, and a longitudinal axis; and   a circular plate coupled to the second end of the shaft, the circular plate oriented perpendicular to the longitudinal axis,   wherein the shaft defines an opening extending from the first end of the shaft towards the second end of the shaft in a direction generally parallel with the longitudinal axis, the opening having a sidewall with a helical thread.   
     
     
         2 . The anchor of  claim 1 , wherein the circular plate is welded to the shaft. 
     
     
         3 . The anchor of  claim 1 , wherein the circular plate has a circularity of at least 0.95. 
     
     
         4 . The anchor of  claim 1 , wherein the shaft defines a height H and the opening defines a depth D, as measured from the first end of the shaft to a bottom wall of the opening, and wherein D is in a range between 0.25 H and 1.0 H. 
     
     
         5 . The anchor of  claim 1 , wherein the opening comprises a bottom wall spaced apart from the first end of the shaft, and wherein the helical thread extends from the first end of the shaft to a location adjacent to the bottom wall of the opening. 
     
     
         6 . The anchor of  claim 1 , wherein a diameter of the shaft is constant between the first and second ends of the shaft. 
     
     
         7 . A precast concrete structure comprising:
 a concrete body;   an anchor comprising:
 a shaft defining a first end and a second end and a longitudinal axis; and 
 a circular plate coupled to the second end of the shaft, the circular plate oriented perpendicular to the longitudinal axis, 
 wherein the shaft defines an opening extending from the first end towards the second end in a direction generally parallel with the longitudinal axis, the opening having a sidewall with a helical thread, 
 wherein the circular plate is embedded in the concrete body and the shaft extends from the concrete body such that the opening is exposed from the concrete body. 
   
     
     
         8 . The precast concrete structure of  claim 7 , further comprising:
 a threaded insert comprising a threaded shank extending at least partially into the opening of the anchor and coupled to the helical thread; and   a fixture coupled to the concrete body by way of the threaded insert.   
     
     
         9 . The precast concrete structure of  claim 7 , wherein the concrete body comprises a metal mesh and a low-density member, wherein the metal mesh comprises a plurality of openings, and wherein the anchor is disposed in the concrete body such that the circular plate is disposed between the metal mesh and the low-density member, the shaft extends through one opening of the plurality of openings, and the entire circular plate is disposed within a perimeter of the one opening when viewed in a direction parallel to the longitudinal axis. 
     
     
         10 . The precast concrete structure of  claim 7 , wherein the shaft has a single-piece construction, and wherein the circular plate is welded to the second end of the shaft. 
     
     
         11 . The precast concrete structure of  claim 7 , wherein the circular plate has a circularity of at least 0.95. 
     
     
         12 . The precast concrete structure of  claim 7 , wherein the shaft defines a height H and the opening defines a depth D, as measured from the first end of the shaft to a bottom wall of the opening, and wherein D is in a range between 0.2 H and 1.0 H. 
     
     
         13 . The precast concrete structure of  claim 7 , wherein the opening comprises a bottom wall spaced apart from the first end of the shaft, and wherein the helical thread extends from the first end of the shaft towards the bottom wall of the opening. 
     
     
         14 . The precast concrete structure of  claim 7 , wherein a diameter of the shaft is constant between the first and second ends of the shaft. 
     
     
         15 . The precast concrete structure of  claim 7 , wherein the circular plate has an area that is at least 90% of an area of a hypothetical circle circumscribing the circular plate. 
     
     
         16 . A method of installing a precast concrete structure, the method comprising:
 threading an insert into an opening of an anchor, the anchor partially embedded in a precast concrete structure, wherein the anchor comprises a circular plate and a shaft coupled to the circular plate, wherein the circular plate is embedded in the precast concrete structure, and wherein the shaft extends from the precast concrete structure;   lifting the precast concrete structure by applying tensile force to the insert;   positioning the precast concrete structure; and   securing a supporting fixture to the precast concrete structure by capturing a portion of the supporting fixture by a head of the insert while the insert is threaded into the opening.   
     
     
         17 . The method of  claim 16 , wherein the circular plate has a circularity of at least 0.95. 
     
     
         18 . The method of  claim 16 , wherein the anchor has an aspect ratio [D S /D CP ] as measured by a ratio of a diameter D S  of the shaft to a diameter D CP  of the circular plate, in a range of 0.3 and 0.7. 
     
     
         19 . The method of  claim 18 , wherein the anchor has an aspect ratio [H/D CP ] as measured by a ratio of a height H of the shaft to a diameter Der of the circular plate  120 , in a range of 0.5 and 2.0. 
     
     
         20 . The method of  claim 16 , wherein the shaft comprises a first end and a second end, and wherein a diameter of the shaft is constant between the first and second ends of the shaft.