US 7,377,363 B2
Elevator with variable drag for car and counterweight
Michael P. Flynn, Avon, Conn. (US); and Harold Terry, Avon, Conn. (US)
Assigned to Otis Elevator Company, Farmington, Conn. (US)
Appl. No. 10/544,141
PCT Filed Feb. 24, 2003, PCT No. PCT/US03/05700
§ 371(c)(1), (2), (4) Date Jul. 28, 2005,
PCT Pub. No. WO2004/076323, PCT Pub. Date Sep. 10, 2004.
Prior Publication US 2006/0175142 A1, Aug. 10, 2006
Int. Cl. B66B 1/34 (2006.01)
U.S. Cl. 187—284  [187/292; 187/293; 318/77; 318/626; 318/467] 12 Claims
OG exemplary drawing
 
8. An elevator system comprising:
an elevator car;
a counterweight;
a rope connecting said elevator car and said counterweight;
a drag element associated with each of said car and said counterweight; a control controlling the amount of drag between said car and said counterweight through said drag element to control movement of said car and said counterweight under at least some conditions;
wherein said control controls said drag elements based upon the vertical position of said car and said counterweight; and
wherein said control controls said drag elements to ensure that the vertically lower of said car and said counterweight is provided with a lower drag than the vertically higher of said car and counterweight.