Method for reducing rope sway in elevators

A method for controlling rope sway in an elevator, comprising the steps of:

• providing a car for travel in a hoistway, said hoistway having a pit and pair of opposed walls extending vertically upward from said pit, wherein said car includes:
• a bottom;
• a center of gravity having an x and a y coordinate;
• and
• a first and second sheave mounted on said bottom;
• providing a counterweight for traveling between said hoistway walls, wherein said car and said counterweight are connected to one another by a plurality of compensating ropes, said ropes having a first end and a second end;
• providing a pair of compensating rope sheaves, fixed in said pit;
• attaching said first end of said compensating ropes to said counterweight;
• extending said ropes from said counterweight to and around one of said compensating rope sheave, then to and around said first sheave attached to said car, then to and around said second sheave attached to said car, then to and around the other of said compensating rope sheaves, then extending up to said counterweight;
• attaching said second ends of said compensating ropes to said counterweight;
• wherein said first sheave is attached to said bottom a distance away from said x coordinate of said car, and said second sheave is attached to said bottom a distance away from said x coordinate of said car, equal to said distance said first sheave is away from said x coordinate, on the opposite side of said x coordinate as said first sheave;
• wherein said distance said sheaves are attached away from said x coordinate is great enough such that oscillation of said ropes will cause said ropes to contact said wall adjacent to said ropes and thereby dampen the motion of said oscillation.

An elevator, comprising:

• a car, having a center of gravity having an x and a y coordinate;
• a hoistway, having a pair of opposed vertically extending walls, between which said car travels,
• a counterweight, for traveling between said hoistway walls;
• a plurality of ropes, extending between said car and said counterweight;
• a drive, for powering said car and counterweight through said hoistway;
• wherein a first number of said ropes is attached to said car a distance away from said x coordinate;
• wherein a second number of said ropes are attached to said car a distance away from said x coordinate, equal to said distance said first number of ropes are away from said x coordinate, on the opposite side of said x coordinate as said first number of ropes;
• and
• wherein said distance said ropes are attached away from said x coordinate is great enough such that oscillation of said ropes will cause said ropes to contact said wall adjacent to said ropes and thereby limit the motion of said oscillation.