Patent ID: 6540068
Filing Date: 2003-04-01
Classification: E05D,E05Y,F16C

Abstract:
For a roller assembly of an apparatus selected from an elevator, an escalator, or a movable track apparatus having a predetermined path for transporting cargo in alternating fashion between at least two fixed points, the apparatus including a first element having an axis of rotation for the roller assembly and a second element which is engaged by the roller assembly, the second element having a shape and surface characteristic that are defined for engaging the roller assembly, the roller assembly having an uninstalled condition, and having operative conditions in which the roller assembly is disposed about the axis of rotation in the installed condition, the roller assembly having a defined path of movement with respect to the second element under at least one operative condition which includes a plurality of predetermined location points, the roller assembly having a rim assembly having a first rolling surface facing outwardly which adapts the roller assembly to engage the second element along the defined path for permitting relative movement between the first and second elements along the defined path while transmitting forces between the elements, a rim assembly disposed about the axis of rotation which comprises:a freestanding rim extending axially and circumferentially with respect to the axis of rotation about the rim assembly, the rim having a second surface on the rim assembly which faces outwardly and which extends circumferentially and axially and which adapts the rim to receive a ring of material, and; the rim assembly in the uninstalled condition having structural features disposed between the first rolling surface and the rim which include a first layer of a first material and further include a structural feature selected from the group consisting of at least one cavity, at least one material different from the material of the first layer, and both at least one cavity and at least one material different from the material of the first layer, the rim assembly further including a ring in solid form in the uninstalled condition and under operative conditions of the rim assembly, the ring extending inwardly at least in part from the first rolling surface to the second surface of the rim, the ring extending circumferentially and axially about the rim and having an outwardly facing surface which includes the rolling first surface for engaging the second element, the ring in solid form including at least the first layer containing the first material, the first layer having at least a sufficient radial depth to form at least part of the outwardly facing rolling surface and provide the surface with a durability characteristic, the first material having a first radial sfiffness characteristic, the ring in solid form having a support region for the first rolling surface associated with each operative condition of the roller assembly which is defined by the position of the ring, the support region having boundaries extending radially through the ring with respect to the axis of rotation from the first rolling surface toward the second surface of the rim, the support region including only that portion of any cavities in the rim assembly into which the part of the ring inwardly of the first rolling surface radially deforms under a particular operative condition and not the remainder of any such cavity; wherein the rim is formed of a material having a second radial stiffness characteristic under operative conditions which is greater than the first radial stiffness characteristic of the material of the ring; wherein the first material of the first layer of the ring necessarily fills a larger portion of said support region under operative conditions than does said material in the uninstalled condition of the roller assembly which causes at least one operative characteristic selected from the group consisting of operative characteristics relating to the bulk behavior of the rim assembly and operative characteristics related to the surface behavior of the rim assembly to differ from a reference operative characteristic that corresponds to said at least one operative characteristic and that is for a rim assembly that is the same as said rim assembly except for having said support region and any cavities into which the ring deforms entirely filled with said first material.