US 12,226,813 B2
Tapered structure construction
Eric D. Smith, Boulder, CO (US); Rosalind K. Takata, Denver, CO (US); Alexander H. Slocum, Bow, NH (US); and Samir A. Nayfeh, Shrewsbury, MA (US)
Assigned to Keystone Tower Systems, Inc., Denver, CO (US)
Filed by Keystone Tower Systems, Inc., Denver, CO (US)
Filed on Feb. 6, 2023, as Appl. No. 18/164,826.
Application 18/164,826 is a continuation of application No. 17/199,019, filed on Mar. 11, 2021, granted, now 11,571,727.
Application 17/199,019 is a continuation of application No. 15/851,472, filed on Dec. 21, 2017, granted, now 10,974,298, issued on Apr. 13, 2021.
Application 15/851,472 is a continuation of application No. 14/978,175, filed on Dec. 22, 2015, granted, now 10,195,653, issued on Jan. 16, 2019.
Application 14/978,175 is a continuation of application No. 13/623,817, filed on Sep. 20, 2012, granted, now 9,302,303, issued on Mar. 16, 2016.
Claims priority of provisional application 61/537,013, filed on Sep. 20, 2011.
Prior Publication US 2023/0249236 A1, Aug. 10, 2023
Int. Cl. B21B 39/02 (2006.01); B21C 37/12 (2006.01); B21C 37/18 (2006.01)
CPC B21B 39/02 (2013.01) [B21C 37/124 (2013.01); B21C 37/126 (2013.01); B21C 37/185 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A device for fabricating a frusto-conical structure, the device comprising:
a drive system including two positioners and a table, each of the two positioners coupled to the table, each of the two positioners rotatably coupled to the table and rotatably coupled relative to the ground;
a curving device operable to impart curvature to a planar form of stock material; and
a control system in communication with the two positioners, the control system configured to activate the two positioners in coordination with one another to move the planar form of the stock material in a combination of translational motion and rotational motion into the curving device to form the stock material into the frusto-conical structure having a virtual peak located at a point where a taper of the frusto-conical structure being formed would decrease to zero if the frusto-conical structure were not truncated.