Sheave for use in an elevator system

An assembly for use in an elevator system, comprising:

• a belt having a width;
• and
• a sheave that supports the belt and is rotatable about a central axis as the belt moves, the sheave including a crowned belt guiding surface having a width that extends between edges on opposite sides of the sheave, the entire belt guiding surface being a single piece of material that presents a continuous, uninterrupted surface, the belt guiding surface having a central portion that has a width across which the belt guiding surface is aligned parallel to the central axis so as to be at least partially equidistant from the central axis, and side portions extending from the central portion toward corresponding edges of the sheave that are curved relative to the central axis, wherein the width of the central portion of the belt guiding surface is equal to approximately two times the difference between the belt width and one-half the width of the belt guiding surface.

A sheave for use in an elevator system, comprising:

• a sheave body have a central axis and a crowned belt guiding surface including a selected reference point, the crowned belt guiding surface including a surface profile extending in an axial direction along at least a portion of the belt guiding surface, the surface profile having a central portion, first side portions extending away from opposite edges of the central portion toward corresponding edges of the sheave and second side portions extending away from the first side portions toward the corresponding edges of the sheave, the central portion having a width across which the surface profile has a parallel alignment with the sheave central axis, the first side portions having a curved profile and the second side portions have a linear profile, wherein the first side portions have a surface profile defined as an nth degree polynomial of a distance from the selected reference point on the belt guiding surface, wherein n is a number greater than two.