HK1194052B - Non-linear stiffness roller assembly - Google Patents

Description

Nonlinear stiffness roller assembly

Technical Field

The present disclosure relates generally to elevator systems and, more particularly, to a roller and guide rail assembly for an elevator.

Background

A typical elevator system includes an elevator car and a counterweight, both suspended on opposite ends of hoisting ropes, belts, cables, etc., and movably disposed within an elevator hoistway. The elevator system also includes a set of guide rails extending substantially the length of the hoistway and disposed on opposite sides of the hoistway to evenly guide the elevator car therethrough. A roller guide assembly rigidly coupled to the elevator car is configured with rollers that roll along the guide rails as the elevator car travels through the hoistway. The design of the roller guide assemblies and associated rollers may be the most influential variable in improving ride quality of an elevator due to their direct interaction with the guide rails.

Various factors may affect the ride quality experienced by passengers of an elevator car as it travels through an elevator hoistway. Wherein the elevator car may be subjected to lateral vibrations or relatively low offset loads when the rollers of the roller guide assembly move over any unevenness or imperfections in the guide rails. The elevator car may also be subjected to higher offset loads caused by, for example, any significant movement of passengers within the elevator car, loading and unloading of passengers, etc. Currently existing elevator systems employ different roller guide configurations such as suspension mechanisms and/or elastomeric roller materials to provide sufficient stiffness and dampen offset loads that cause ride discomfort. While such roller guide mechanisms may provide sufficient stiffness and damping, there is still room for improvement.

Some elevator systems employ roller guide assemblies having suspension mechanisms that support the rollers on a movable roller axis. In particular, the suspension (suspension) flexibly biases the roller against the associated guide rail so that any vibrations caused by defects in the guide rail or low offset loads are sufficiently damped by the suspension before reaching the elevator car. While suspension-based assemblies may adequately dampen lower offset loads, these roller guide assemblies do not provide sufficient stiffness for higher offset loads. Rather, the suspension-based assembly provides a safety device or stop that limits further travel of the suspension and prevents undesirable contact between the roller guide assembly and the corresponding rail. Suspension-based roller guide assemblies tend to be more costly to implement and maintain due to the complexity and number of components involved.

Other types of elevator systems employ roller guide assemblies in which the rollers have fixed roller axes. Fixed axis rollers are typically provided with an elastomeric material having a generally tapered or rounded surface that serves to cushion contact between the roller and the rail. The tapered or rounded contact area as shown in fig. 1 provides a non-linear increase in stiffness when the elastomeric material deforms under load and conforms to the flat surface of the rail (also referred to as hertzian contact) as compared to suspension-based assemblies. While hertzian contact rollers may be a lower cost solution that also provides non-linearly increasing stiffness in response to offset loads, hertzian contact rollers still lack the ability to provide a sufficiently sharp stiffness transition at the desired deflection point. Furthermore, the range of stiffness exhibited by the rollers that can be adjusted to meet damping criteria for different system configurations is very limited. Moreover, the stiffness of such fixed roller guide assemblies is highly dependent on the material properties of the elastomer. For example, the stiffness of the elastomeric material of the hertzian contact roller may vary significantly with changes in ambient temperature.

Disclosure of Invention

According to one embodiment of the present disclosure, a roller apparatus is provided. The roller apparatus may include: a support wheel configured to rotatably couple the roller apparatus to the roller shaft; and an elastic member disposed radially around the supporting wheel and configured to contact the guide rail under loads of different magnitudes. The resilient member may include a first section having a first diameter and a second section having a second diameter. The first section may be forced to flex in response to a load within a first load range, while the second section may be forced to flex in response to a load within a second load range. The resilient member may exhibit a step increase in stiffness with increasing load.

In another embodiment of the roller apparatus described above, each of the first and second sections of the resilient member may be formed from a single resilient material.

In a refinement of any of the roller apparatus embodiments described above, the first diameter may be greater than the second diameter, and the second load range may be greater in magnitude than the first load range. The step increase in stiffness may occur when the load is outside a first load range.

In a refinement of any of the roller apparatus embodiments described above, the step increase in stiffness may occur when the first section flexes and the second section is in contact with the rail.

In a refinement of any of the roller apparatus embodiments described above, the first section may comprise two or more radially extending surfaces and the second section may be disposed therebetween.

In a refinement of any of the roller apparatus embodiments described above, the resilient member may comprise at least one groove distinguishing the first segment from the second segment. The groove may be configured to reduce the stiffness of at least one of the first and second sections.

In a refinement of any of the above embodiments of the roller apparatus, the groove may be provided at one side of the resilient member such that the first section is radially distinct from the second section. A step increase in stiffness may occur when the load exceeds the first load range and causes the groove to substantially close.

In a refinement of any of the roller apparatus embodiments described above, the resilient member may further comprise a third section having a third diameter, the third section being forced to flex in response to a load within a third load range. The third diameter may be less than each of the first and second diameters, and the third load range may be greater in magnitude than each of the first and second load ranges.

According to another embodiment of the present disclosure, a guide assembly is provided. The guide assembly may include: a base plate having a plurality of roller shafts rigidly coupled thereto; and a plurality of rollers rotatably coupled to the roller shaft. Each roller may include a resilient member configured to contact the rail under loads of different magnitudes and including a first section having a first diameter and a second section having a second diameter. The resilient member may exhibit a step increase in stiffness with increasing load.

In another embodiment of the steering assembly, the first section may be forced to flex in response to loads within a first load range, and the second section may be forced to flex in response to loads within a second load range. The first diameter may be greater than the second diameter, and the second load range may be greater in magnitude than the first load range.

In a refinement of any of the above-described guide assembly embodiments, each of the first and second sections of the resilient member may be formed from a single resilient material.

In a refinement of any of the above-described guide assembly embodiments, the first section may comprise two or more radially extending surfaces and the second section may be disposed therebetween.

In a refinement of any of the above-described guide assembly embodiments, the resilient member may comprise at least one groove distinguishing the first section from the second section. The groove may be configured to reduce the stiffness of at least one of the first and second sections.

In a refinement of any of the above-described guide assembly embodiments, the plurality of rollers may include a first roller, a second roller, and a third roller. The first and second rollers may be aligned with one another at the edge of the base plate to rollingly receive opposite surfaces of the rail therebetween. A third roller may be positioned vertically between the first and second rollers to rollingly receive an edge of the guide rail thereagainst.

In a refinement of any of the above-described guide assembly embodiments, the resilient member of the third roller may comprise at least one groove disposed at one side thereof such that the first segment is radially distinct from the second segment.

According to yet another embodiment of the present disclosure, an elevator system is provided. The elevator system may include two or more guide rails disposed vertically within a hoistway, an elevator car movably disposed between the guide rails, and a plurality of guide assemblies disposed between the elevator car and the guide rails. Each guide assembly may include a base plate rigidly coupled to the elevator car and a plurality of rollers rotatably coupled to the base plate. Each roller may include a resilient member configured to contact the rail under loads of different magnitudes and exhibit a step increase in stiffness with increasing load.

In another embodiment of the elevator system described above, each guide rail can include at least one flat surface and at least one raised surface extending substantially the length of the guide rail and configured to interface with at least one of the resilient members. The resilient member may be configured to exhibit a first stiffness in response to a load in a first load range when contacting the protrusion surface and a second stiffness in response to a load in a second load range when contacting both the flat surface and the protrusion surface. The second load range may be greater in magnitude than the first load range.

In a refinement of any of the elevator system embodiments described above, the resilient member may include a first section having a first diameter that is forced to flex in response to a load in a first load range and a second section having a second diameter that is forced to flex in response to a load in a second load range. The first diameter may be greater than the second diameter, and the second load range may be greater in magnitude than the first load range.

In a refinement of any of the elevator system embodiments described above, the plurality of rollers may include at least two front-to-back (front-to-back) rollers aligned with each other at an edge of the base plate to rollingly receive opposing surfaces of the guide rail therebetween and limit forward and backward movement of the elevator car.

In a refinement of any of the elevator system embodiments described above, the plurality of rollers may include at least one lateral roller positioned vertically between the forward and rearward rollers to rollingly receive an edge of the guide rail against and limit lateral movement of the elevator car.

These and other aspects of the disclosure will become more apparent upon reading the following detailed description in conjunction with the accompanying drawings.

Drawings

FIG. 1 shows a partial cross-sectional view of a prior art roller apparatus and a graph of its flexural properties;

fig. 2 illustrates a perspective view of an exemplary elevator system;

FIG. 3 illustrates a perspective view of an exemplary roller guide assembly;

4-5 illustrate cross-sectional views of two exemplary front-to-back rollers;

FIG. 6 illustrates a cross-sectional view of an exemplary lateral roller;

FIGS. 7-10 show partial cross-sectional views of additional roller embodiments and graphs of their flexural properties;

FIGS. 11-13 show partial perspective views of another alternative roller embodiment; and

figures 14-15 show cross-sectional views of yet another roller embodiment applied to a rail having a modified surface.

While the disclosure is susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the disclosure to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the scope of the disclosure.

Detailed Description

Referring now to fig. 2, a diagram of an exemplary elevator system 100 is provided. It should be understood that the type of elevator system 100 shown in fig. 2 is for illustrative purposes only and provides context for the various components of a typical elevator system. Other components of the elevator system not necessary to understand the present disclosure are not described.

As shown in fig. 2, an elevator system 100 may be disposed within a hoistway 102 and provided with a traction member 104, an elevator car frame 106, an elevator car 108, a roller guide assembly 110, and guide rails 112. More specifically, the traction member 104 may be a cable secured between a car frame 106 and a counterweight (not shown) movably mounted within the hoistway 102 as shown. However, in all elevator system embodiments herein, the traction members may comprise belts or other suspension devices.

Similarly, although the car 108 and car frame 106 are shown as separate but joined entities, in all elevator system embodiments herein, the car and car frame may be a unitary structure. The car 108 may be coupled to the car frame 106 and configured to travel up and down the hoistway 102 by forces transmitted to the car frame 106 through the cable 104. Roller guides 110 may be attached to the car frame 106 and configured to vertically guide the elevator car 108 along guide rails 112 through the hoistway 102.

Turning to fig. 3, an exemplary roller guide assembly 110 applicable to the elevator system 100 of fig. 2 is provided. As shown, the guide assembly 110 may include a base plate 200 and a plurality of rollers 202 and 204. The base plate 200 may include a plurality of apertures 206, and the base plate 200 may be rigidly mounted to the elevator car frame 106 or the car 108 through the apertures 206 using bolts, screws, or the like. The base plate 200 may also provide a plurality of roller support members 208, the roller support members 208 each having a roller axle 210 rigidly coupled thereto. Each roller 202 and 204 may be rotatably mounted about a roller axle 210 and on a corresponding support member 208. Further, the rollers 202 and 204 may be arranged to reduce any lateral travel of the elevator car 108 relative to the guide rail 112 and further dampen any vibration between the rollers 202 and 204 and the guide rail 112. As shown in fig. 3, for example, the guide assembly 110 may provide a first roller 202 and a second roller 203, both the first roller 202 and the second roller 203 being arranged at the edge of the base plate 200 in line with each other. Specifically, the first roller 202 and the second roller 203 may be configured to rollingly receive one of the guide rails 112 therebetween and limit any fore-aft travel of the elevator car 108 relative to the guide rails 112. The guide assembly 110 may additionally provide a third roller 204 disposed vertically between the first roller 202 and the second roller 203. As with the first roller 202 and the second roller 203, the third roller 204 may be configured to rollingly receive and abut an edge of the guide rail 112 so as to limit any lateral travel of the elevator car 108 relative to the guide rail 112.

Referring now to fig. 4 and 5, an exemplary embodiment of the first roller 202 and the second roller 203 of fig. 3 is provided. However, it should be understood that the rollers 202, 203 shown in fig. 4 and 5 may also be used as the third roller 204 of the roller guide assembly 110 shown in fig. 3. As shown, each of the first roller 202 and the second roller 203 may include a support wheel 212 and a resilient member 214. Each support wheel 212 may interface with roller shaft 210 using ball bearings, roller bearings, or any other arrangement suitable for reducing rotational friction between rollers 202, 203 and roller shaft 210. The resilient member 214 may be radially fitted around the support wheel 212 and configured to compliantly abut against a surface of the guide rail 112. The resilient member 214 may be formed of rubber, polytetrafluoroethylene (polytetrafluoroethane), urethane such as polyether urethane, polyester urethane, or any other resilient material designed to cause an increase in stiffness when in contact with the surface of the rail 112 and subjected to an offset load. The stiffness may be defined by the rate of change in load relative to the change in deflection of the resilient material. Further, the resilient member 214 may include a geometry, such as a rib, lip, groove, etc., configured to exhibit a non-linear or stepped increase in stiffness when interfacing with a flat surface of the rail 112.

Still referring to fig. 4 and 5, each resilient member 214 may include at least a first section 216 having a first diameter and a second section 218 having a second diameter, both formed from a single resilient material. The first section 216 may be configured to flex in response to a load having a magnitude within a first load range, and the second section 218 may be configured to flex in response to a load having a magnitude within a second load range. In the exemplary embodiment of fig. 4 and 5, for example, first section 216 of each roller 202, 203 may be larger in diameter than second section 218. Thus, when rollers 202, 203 are subjected to a lesser load having a magnitude within a first load range, first section 216 of rollers 202, 203 may provide sufficient stiffness against rail 112, as shown in fig. 4. However, when the rollers 202, 203 are subjected to large loads having magnitudes outside of the first load range or within the second load range, sufficient stiffness may require flexing of the first section 216 and direct contact between the second section 218 and the rail 112. As shown in fig. 5, for example, loads in a higher or second load range may cause the first section 216 of the second roller 203 to fully flex and the second section 218 to be in direct contact with the rail 112. Correspondingly, when the second section 218 having a smaller diameter is in direct contact with the rail 112, higher offset loads may result in a step increase in stiffness. The resilient member 214 may additionally include a geometry having one or more grooves 220 disposed between the radially extending surfaces of the first and second portions 216, 218, i.e., the grooves 220 may be disposed circumferentially around the rollers 202, 203.

Moreover, the depth, width, and/or number of grooves 220 provided on the resilient member 214 may be modified to adjust the stiffness exhibited by the rollers 202, 203. More specifically, grooves 220 may be provided to reduce the stiffness exhibited by rollers 202, 203.

Turning to fig. 6, an exemplary embodiment of the third roller 204 of fig. 3 is provided. However, it should be understood that the rollers 204 shown in fig. 6 may also be used as the first and second rollers 202 and 203 of the roller guide assembly 110 shown in fig. 3. As with the first and second rollers 202, 203 of the previous embodiments, the third roller 204 may include a support wheel 212, the support wheel 212 reducing rotational friction between the roller 204 and the corresponding roller axle 210. The third roller 204 may also include a resilient member 314, the resilient member 314 being radially fitted around the support wheel 212 and configured to readily snugly abut an edge of the guide rail 112, as shown. As in the previous embodiments, the resilient member 314 may be formed from a single resilient material, such as rubber, polytetrafluoroethylene, urethane, such as polyether based urethane, polyester based urethane, or any other resilient material designed to cause an increase in stiffness when in contact with the surface of the rail 112 and subjected to an offset load. Further, the resilient material may include a geometry that enables the roller 204 to exhibit a non-linear increase in stiffness when interfacing with the rail 112. As shown in fig. 6, for example, the resilient member 314 may include a first section 316 having a first or larger diameter and a second section 318 having a second or smaller diameter. Unlike previous embodiments, first segment 316 and second segment 318 may be distinguished by a groove 320 that extends at least partially through one side of resilient member 314. However, similar to the previous embodiments, the groove 320 may be configured to adjust (e.g., reduce) the stiffness exhibited by the rollers 202 and 204. The first section 316 may be configured to flex in response to loads that are small in magnitude or within a first load range, and the second section 318 may be configured to flex in response to loads that are large in magnitude or within a second load range. Thus, the first section 316 may provide sufficient stiffness to the guide rail 112 when the roller 204 is subjected to a lesser load having a magnitude within the first load range. However, both the first section 316 and the second section 318 may be used to provide a non-linear increase in stiffness when the roller 204 is subjected to loads having a magnitude that exceeds the first load range. More specifically, a non-linear or step increase in stiffness may occur when the rail 112 flexes the first section 316, substantially closes the groove 320, and causes, at least in part, some flexing of the second section 318. In alternative embodiments of the roller 204, the depth, width, and/or number of grooves 320 provided on the resilient member 314 may be modified to adjust the stiffness exhibited by the roller 204. In an alternative modification of the roller guide assembly 110, the third roller 204 may employ the resilient members 214 of the first and second rollers 202, 203 of fig. 4 and 5. In a further modification of the guide assembly 110, the first roller 202 and the second roller 203 may employ the resilient member 314 of the third roller 204 of fig. 6. Of course, in other embodiments of the guide assembly 110, two or more of the rollers 202, 204 may employ one of the resilient members 214, 314, while the third roller 202, 204 may employ the other of the resilient members 214, 314.

Referring now to fig. 7-10, additional flexural properties of the roller geometry and corresponding cross-sectional views are provided. Any one or more of the roller geometries shown in fig. 7-10 may be used as any of the rollers 202 and 204 shown in the embodiment disclosed in fig. 3. Thus, in some embodiments of the guide assembly 110, two or more of the rollers 202 and 204 may employ one of the roller geometries shown in FIGS. 7-10, while the third roller 202 and 204 may employ another of the roller geometries. In other embodiments, all three rollers 202-204 in the guide assembly 110 may include the same roller geometry or different roller geometries. Finally, any one or more of the resilient members 414,514, 614, 714 shown in fig. 7-10 may be formed from a material such as rubber, polytetrafluoroethylene, urethane such as polyether based urethane, polyester based urethane, or any other resilient material designed to cause an increase in stiffness when in contact with the surface of the rail 112 and subjected to an offset load.

In the cross-sectional view of fig. 7, the resilient member 414 may include a first section 416 having a larger diameter than a second section 418. First section 416 and second section 418 may be further distinguished by a set of grooves 420 disposed therebetween. In other words, the groove 420 may be disposed between the radially extending surfaces of the first and second portions 416, 418, i.e., the groove 420 may be circumferentially disposed. Similar to the previous embodiments, the groove 420 may be configured to adjust (e.g., reduce) the stiffness exhibited by the rollers 202 and 204. The resilient member 414 of fig. 7 may provide a non-linear increase in stiffness in response to an increase in the load exerted thereon by the rail 112 as compared to the stiffness of the prior art embodiment of fig. 1. More specifically, the resilient member 414 may exhibit different stiffness characteristics under different ranges of loads when in contact with the rail 112. For example, the resilient member 414 may exhibit a first stiffness when the rail 112 interfaces with the first segment 416 at loads within the first load range I. The resilient member 414 may also exhibit a second stiffness when the rail 112 interfaces with the second segment 418 at a generally greater load over a second load range II that is greater than the first load range I. Thus, the resilient member 414 may exhibit a step increase in stiffness once the applied load exceeds a first load range I corresponding to deflection of the first section 416 and falls within a second load range II corresponding to at least partial deflection of the second section 418.

The resilient member 514 of fig. 8 may include a first section 516 having a first diameter, a second section 518 having a second diameter, and a third section 519 having a third diameter, distinguished by two sets of grooves 520. In other words, the groove 520 may be disposed between radially extending surfaces of the first portion 516, the second portion 518, and the third portion 519, i.e., the groove 520 may be circumferentially disposed. Similar to the previous embodiments, the groove 520 may be configured to adjust (e.g., reduce) the stiffness exhibited by the rollers 202 and 204. Specifically, the first diameter may be larger than the second diameter, and the third diameter may be sized smaller than each of the first and second diameters. The resilient member 414 may exhibit different stiffness characteristics based on the magnitude of the load applied thereto by the rail 112 and the particular sections 516, 518, 519 in contact with the rail 112. Specifically, the resilient member 514 may exhibit a first stiffness when the rail 112 interfaces with the first segment 516 with loads within a first load range I, a second stiffness when the rail 112 interfaces with the second segment 518 with loads within a second load range II (which is greater than the first load range I), and further a third stiffness when the rail 112 interfaces with the third segment 519 with loads within a third load range III (which is greater than the second load range II). Thus, the resilient member 514 of fig. 8 may exhibit a first step increase in stiffness once the applied load exceeds a first load range I corresponding to deflection of the first section 516 and falls within a second load range II corresponding to at least partial deflection of the second section 518. The resilient member 514 may also exhibit a second step increase in stiffness once the applied load exceeds the second load range II and falls within a third load range III corresponding to at least partial deflection of the third segment 519.

Similar to the embodiment of fig. 6, the resilient member 614 of fig. 9 may include a first segment 616 having a larger diameter than a second segment 618, wherein the first and second segments 616, 618 may be distinguished by a groove 620 extending partially through one side of the resilient member 614. Similar to the previous embodiments, the groove 520 may be configured to adjust (e.g., reduce) the stiffness exhibited by the rollers 202 and 204. As with the previous embodiments, the resilient member 614 of fig. 9 may also provide a non-linear increase in stiffness with a gradual increase in the load applied by, for example, the rail 112. More specifically, the resilient member 614 may exhibit a first stiffness when the rail 112 interfaces with the first segment 616 at loads within the first load range I. The resilient member 614 may also exhibit a second stiffness when the rail 112 substantially closes the groove 620 and at least partially interfaces with the second segment 618 at a generally greater load within a second load range II that is greater than the first load range I. Thus, the resilient member 614 may exhibit a step increase in stiffness once the applied load exceeds a first load range I corresponding to deflection of the first segment 616 and falls within a second load range II corresponding to at least partial deflection of the second segment 618 and substantial closure of the groove 620.

The resilient member 714 of fig. 10 may include a first section 716 having a first diameter, a second section 718 having a second diameter, and a third section 719 having a third diameter. Each of the first, second and third segments 716, 718, 719 can be distinguished by a groove 720 extending partially through one side of the resilient member 714. Similar to the previous embodiments, the groove 720 may be configured to adjust (e.g., reduce) the stiffness exhibited by the rollers 202 and 204. The first diameter may be greater than each of the second diameter and the third diameter, and the third diameter may be sized smaller than each of the first diameter and the second diameter. The resilient member 714 of fig. 10 may exhibit different stiffness characteristics under different ranges of loads when in contact with the rail 112. For example, the resilient member 714 may exhibit a first stiffness when the rail 112 interfaces with the first section 716 at loads within the first load range I. The resilient member 714 may also exhibit a second stiffness when the rail 112 substantially closes the outermost groove 720 and at least partially interfaces with the second segment 718 at a generally greater load within a second load range II that is greater than the first load range I. The resilient member 714 of fig. 10 may additionally exhibit a third stiffness when the rail 112 substantially closes both the outermost and innermost grooves 720 and at least partially interfaces with the third segment 719 at an even greater load within a third load range III that is greater than the second load range II. Thus, the resilient member 714 may exhibit a first step increase in stiffness once the applied load exceeds a first load range I corresponding to deflection of the first section 716 and falls within a second load range II corresponding to substantial closing of the first groove 720 and at least partial deflection of the second section 718. The resilient member 714 may further exhibit a second step increase in stiffness once the applied load exceeds the second load range II and falls within a third load range III corresponding to the substantially closed second groove 720 and the at least partial deflection of the third section 719.

Turning to fig. 11-13, further alternative roller embodiments are provided that can exhibit non-linear stiffness, any one or more of which may be used as any of the rollers 202 and 204 shown in the embodiment disclosed in fig. 3. In the embodiment shown in fig. 11-13, it can be seen that the support wheels 812, 912, 1012 of the rollers 800, 900, 1000 may have a shape that is asymmetric across the radially inner portion thereof. Such asymmetry may be provided to facilitate mounting and assembly of the support wheels 212, 812, 912, 1012 to, for example, a wheel hub or the like. More specifically, the support wheels 212, 812, 912, 1012 may include shoulders for resting the support wheels 212, 812, 912, 1012 thereon when the support wheels 212, 812, 912, 1012 are fitted or pressed onto an associated hub. Further, the radially inner portion of the support wheel 212, 812, 912, 1012 may include a recess sized to receive a snap ring (snap ring) or the like that may be disposed on an outer surface of an associated hub to hold the support wheel 212, 812, 912, 1012 thereagainst. Additionally, like the previously disclosed resilient members 214, 314, 414,514, 614, 714, any of the resilient members 814, 914, 1014 shown in fig. 11-13 may be made of a material such as rubber, polytetrafluoroethylene, urethane such as polyether based urethane, polyester based urethane, or any other resilient material designed to cause an increase in stiffness when in contact with the surface of the rail 112 and subjected to an offset load.

Although the rollers shown in fig. 11-13 are numbered 800, 900 and 1000, respectively, such numbering is for ease of reference. It will be readily appreciated that each of these rollers 800, 900, 1000 may be used as the rollers 202 and 204 of the roller guide assembly 110 shown in fig. 3.

In the embodiment of fig. 11, the roller 800 may generally include a support wheel 812 and a resilient member 814 radially adhered and/or fitted around the support wheel 812. The resilient member 814 may include a first section 816 having a first diameter and a second section 818 having a second diameter, both formed from a single resilient material. As shown, the first diameter may be larger in diameter than the second diameter, and thus, the first section 816 may be forced to flex in response to a first or lower load range, while the second section 818 may be forced to flex in response to a second or higher load range. The resilient member 814 may additionally include a groove 820 adjacent the first segment 816 and extending partially through a side of the resilient member 814. In other words, the grooves 820 may extend axially. The side grooves 820 of fig. 11 may be used to further reduce the stiffness of at least the first segment 816 and reduce the first load range. As in the previous embodiments, the geometry provided in fig. 11 may exhibit a non-linear or stepped increase in stiffness of the resilient member 814 when the magnitude of the load exceeds a first load range corresponding to deflection of the first segment 816 and falls within a second load range corresponding to at least partial deflection of the second segment 818.

The roller 900 of fig. 12 may similarly include a support wheel 912 and a resilient member 914 disposed about the support wheel 912. In contrast to the embodiment of fig. 11, the support wheel 912 of fig. 12 may provide a lip 921 and the notch 922 provided on the inner surface of the resilient member 914 may fit over the lip 921 to achieve a more secure fit. As in the previous embodiments, the resilient member 914 may provide a first section 916 having a first diameter and a second section 918 having a second diameter, both formed from a single resilient material. Further, the first diameter may be larger in diameter than the second diameter, and thus, the first section 916 may be forced to deflect in response to a first or lower load range, while the second section 918 may be forced to deflect in response to a second or higher load range. As shown in fig. 12, the resilient member 914 may be provided without any grooves, except for the recessed region that distinguishes the first section 916 from the second section 918, in order to provide greater rigidity. Moreover, the geometry of the first and second sections 916, 918 of the illustrated resilient member 914 may exhibit a non-linear or stepped increase in stiffness when the magnitude of a load placed thereon exceeds a first load range corresponding to deflection of the first section 916 and falls within a second load range corresponding to at least partial deflection of the second section 918.

Additionally, the roller 1000 of fig. 13 may include a support wheel 1012 and a resilient member 1014 disposed about the support wheel 1012. In contrast to the previous embodiments, the bearing wheel 1012 of fig. 13 may provide a radial recess 1023 into which the resilient member 1014 may fit to achieve greater support. The elastic member 1014 may provide the first section 1016 and the second section 1018 with unequal diameters, both formed from a single elastic material. The resilient member 1014 may also provide two grooves 1020 that further distinguish the first section 1016 from the second section 1018. In other words, the groove 1020 may be disposed between the radially extending surfaces of the first and second segments 1016, 1018, i.e., the groove 1020 may be circumferentially disposed. Similar to the previous embodiments, the groove 1020 may be configured to adjust (e.g., reduce) the stiffness exhibited by the rollers 202 and 204. As shown, the first section 1016 may be rounded and configured to have a minimum diameter that is less than the diameter of the second section 1018 and a maximum diameter that is greater than the diameter of the second section 1018. Because the first section 1016 has a maximum diameter that is greater than the diameter of the second section 1018, the first section 1016 may be forced to deflect in response to a first or lower load range, while the second section 1018 may be forced to deflect in response to a second or higher load range. As with the previous embodiments, the geometry of the first and second sections 1016, 1018 of the illustrated resilient member 1014 may exhibit a non-linear or stepped increase in stiffness when the magnitude of the load placed thereon exceeds a first load range corresponding to at least partial deflection of the first section 1016 and falls within a second load range corresponding to at least partial deflection of the second section 1018.

Referring now to fig. 14 and 15, yet another exemplary arrangement of rollers 1100 is provided. Any of the illustrated rollers 1100 may be used as any of the rollers 202 and 204 shown in the embodiment of fig. 3, provided that the associated guide track 112 provides geometric features comparable to, for example, the raised surface 115 disclosed in fig. 14 and 15. Correspondingly, any geometric feature comparable to, for example, the raised surface 115 shown in fig. 14 and 15 can be provided to any of the guide rails 112 in the elevator system 100 disclosed in fig. 2. Also, like the previously disclosed resilient members 214, 314, 414,514, 614, 714, 814, 914, 1014, the resilient member 1114 of fig. 14 and 15 may be formed from a material such as rubber, polytetrafluoroethylene, urethane such as polyether based urethane, polyester based urethane, or any other resilient material designed to cause an increase in stiffness when in contact with the surface of the rail 112 and subjected to an offset load.

Although the rollers are shown in fig. 14 and 15 as being numbered 1100, such numbering is for ease of reference. It will be readily appreciated that the roller 1100 may be used as the rollers 202 and 204 of the roller guide assembly 110 shown in fig. 3.

As in the previous embodiment, each roller 1100 may include a support wheel 1112 rotatably mounted to the roller axle 1110 and a resilient member 1114 fitted radially around the support wheel 1112. The rollers 1100 can be arranged in line with one another to receive a surface of the guide rail 112 therebetween and limit fore and aft travel of the elevator car 108 relative to the guide rail 112. More specifically, the resilient member 1114 of fig. 14 and 15 may include a generally flat outer surface that contacts a surface of the rail 112 under varying deflection loads. Moreover, the surface of rail 112 may include a non-linear or stepped increase geometry that physically interacts with resilient member 1114 to exhibit stiffness in response to an increasing deflection load. For example, each rail 112 may include at least one flat surface 113 and at least one raised surface 115 that extend substantially the length of the rail 112 and are positioned to interface with the resilient member 1114. Alternatively, the guide rail 112 may include two or more raised surfaces 115 having different dimensions. In other alternatives, the protrusion surface 115 may include a curved portion, a rounded portion, an angled portion, a chamfered portion, a ribbed portion, a ridged portion, or any combination thereof.

As shown in fig. 14, lower deflection loads may be adequately damped by the first or relatively lower stiffness exhibited when the resilient member 1114 merely pushes and/or rolls against the raised surface 115 of the rail 112. As shown in fig. 15, higher offset loads may be adequately damped by the second or relatively greater stiffness exhibited when the resilient member 1114 flexes and pushes against the protrusion surface 115 and at least a portion of the flat surface 113 of the rail 112. Further, as the magnitude of the offset load increases, the geometry of the interface between the roller 110 and the rail 112 may be configured such that the contact area therebetween increases in a step-like manner. As the contact area between the resilient member 1114 and the rail 112 increases in a step-wise manner, the resulting stiffness may also increase in a step-wise manner. In an alternative modification, the embodiment of fig. 14 and 15 may additionally provide a third roller disposed vertically between the first and second rollers 1100 to receive an edge of the guide rail 112 and limit lateral travel of the associated elevator car 108. In other modifications, the edge of the guide rail 112 may similarly include a flat surface and a raised surface, and the third roller may contact these surfaces under different offset loads and exhibit a step increase in stiffness.

INDUSTRIAL APPLICABILITY

From the foregoing, it can be seen that the present disclosure sets forth an elevator system having a novel roller and guide assembly that improves overall ride quality in an elevator car with a more cost effective solution. Elevator cars are typically subjected to a low degree of lateral vibration and high offset loads, which can cause undesirable contact between the safety stops and the guide rails. The roller apparatus and roller guide assembly of the present disclosure provides optimal stiffness in both the lower and higher ranges of offset loads using resilient members constructed of only a single resilient material and inexpensive roller suspension components. The assemblies disclosed herein accomplish this by providing the resilient member and rail surface with a geometry that exhibits a non-linear or stepped increase in stiffness in response to an increase in load.

While only certain embodiments have been set forth, alternatives and modifications will be apparent to those skilled in the art in light of the foregoing description. These and other alternatives are considered equivalents and within the scope of this disclosure.

Claims (15)

1. A roller apparatus (202, 203, 204, 800, 900, 1000) comprising:

a support wheel (212, 812, 912, 1012) comprising a bearing that is circular in cross-section and configured to rotatably couple the roller apparatus (202, 203, 204, 800, 900, 1000) to a rigid roller shaft (210); and

a resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) disposed radially around the support wheel (212, 812, 912, 1012) and configured to contact a rail (112) under loads of different magnitudes, the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) comprising a first section (216,316, 416, 516,616, 716, 816, 916, 1016) having a first diameter and a second section (218, 318, 418,518, 618, 718, 818, 918, 1018) having a second diameter, the first section (216,316, 416, 516, 816, 916, 1016) comprising two or more radially extending surfaces and the second section (218, 318, 418,518, 818, 918, 1018) Disposed between the two or more radially extending surfaces, the first segment (216,316, 416, 516, 816, 916, 1016) being larger in diameter than the second segment (218, 318, 418,518, 818, 918, 1018), the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) being forced to flex in response to a load in a first load range, the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018) being forced to flex in response to a load in a second load range, the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) being configured to exhibit a step increase in stiffness with a gradual increase in load.

2. The roller apparatus (202, 203, 204, 800, 900, 1000) of claim 1, wherein each of the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) and the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018) of the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) is formed from a single resilient material.

3. The roller apparatus (202, 203, 204, 800, 900, 1000) of claim 1, wherein the first diameter is greater than the second diameter and the second load range is greater in magnitude than the first load range, the step increase in stiffness occurring when the load is outside the first load range.

4. The roller apparatus (202, 203, 204, 800, 900, 1000) of claim 3, characterized in that the step increase in stiffness occurs when the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) flexes and the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018) contacts the rail (112).

5. The roller apparatus (202, 203, 204, 800, 900, 1000) of claim 1, characterized in that the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) includes at least one groove (220, 320,420, 520, 620, 720, 820, 1020) distinguishing the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) from the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018), the groove (220, 320,420, 520, 620, 720, 820, 1020) configured to reduce the friction between the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) and the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018).

6. The roller apparatus (202, 203, 204, 800, 900, 1000) of claim 1, wherein the resilient member (514, 714) further comprises a third section (519,719) having a third diameter that is forced to flex in response to a load within a third load range, the third diameter being less than each of the first and second diameters, the third load range being greater in magnitude than each of the first and second load ranges.

7. A steering assembly (110), comprising:

a base plate (200) having a plurality of roller shafts (210) rigidly coupled thereto; and

a plurality of rollers (202, 203, 204, 800, 900, 1000) rotatably coupled to the roller shaft (210), each roller (202, 203, 204, 800, 900, 1000) comprising a resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014), the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) configured to contact a rail (112) under loads of different magnitudes and comprising a first section (216,316, 416, 516,616, 716, 816, 916, 1016) having a first diameter and a second section (218, 318, 418,518, 618, 718, 818, 918, 1018) having a second diameter, the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) configured to exhibit a stepped increase in stiffness with a gradual increase in load, the first segment (216,316, 416, 516, 816, 916, 1016) comprises two or more radially extending surfaces and the second segment (218, 318, 418,518, 818, 918, 1018) is disposed between the two or more radially extending surfaces, the first segment (216,316, 416, 516, 816, 916, 1016) being larger in diameter than the second segment (218, 318, 418,518, 818, 918, 1018).

8. The steering assembly (110) of claim 7, wherein the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) is forced to flex in response to a load within a first load range and the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018) is forced to flex in response to a load within a second load range, the first diameter being greater than the second diameter and the second load range being greater in magnitude than the first load range.

9. The guide assembly (110) of claim 7, wherein each of the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) and the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018) of the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) is formed from a single resilient material.

10. The guide assembly (110) of claim 7, wherein the resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014) includes at least one groove (220, 320,420, 520, 620, 720, 820, 1020) distinguishing the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) from the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018), the groove (220, 320,420, 520, 620, 720, 820, 1020) is configured to reduce a stiffness of at least one of the first segment (216,316, 416, 516,616, 716, 816, 916, 1016) and the second segment (218, 318, 418,518, 618, 718, 818, 918, 1018).

11. The guide assembly (110) of claim 7, wherein the plurality of rollers (202, 203, 204, 800, 900, 1000) includes a first roller (202), a second roller (203), and a third roller (204), the first roller (202) and the second roller (203) being aligned with one another at an edge of the base plate (200) to receive opposing surfaces of the guide rail (112) therebetween, the third roller (204) being positioned vertically between the first roller (202) and the second roller (203) to abuttingly receive the edge of the guide rail (112).

12. An elevator system (100), comprising:

two or more guide rails (112) disposed vertically within the hoistway (102);

an elevator car (108) movably disposed between the guide rails (112); and

a plurality of guide assemblies (110) disposed between the elevator car (108) and the guide rail (112), each guide assembly (110) including a base plate (200) rigidly coupled to the elevator car (108) and a plurality of rollers (202, 203, 204, 800, 900, 1000,1100) rotatably coupled to the base plate (200), each roller (202, 203, 204, 800, 900, 1000,1100) including a resilient member (214, 314, 414,514, 614, 714, 814, 914, 1014, 1114), the resilient members (214, 314, 414,514, 614, 714, 814, 914, 1014, 1114) configured to contact the guide rail (112) under varying amounts of load and to exhibit a step increase in stiffness with a gradual increase in load, each guide rail (112) including a step increase that extends substantially a length of the guide rail (112) and is configured to contact at least one of the resilient members (1114) At least one interfacing flat surface (113) and at least one protruding surface (115), the resilient member (1114) being configured to exhibit a first stiffness in response to a load within a first load range when contacting the protruding surface (115) and to exhibit a second stiffness in response to a load within a second load range when contacting both the flat surface (113) and the protruding surface (115), the second load range being greater in magnitude than the first load range.

13. The elevator system (100) of claim 12, wherein the resilient member (214, 314, 414,514, 614, 714, 814, 1014) includes a first section (216,316, 416, 516,616, 716, 816, 916, 1016) having a first diameter that is forced to deflect in response to loads within a first load range and a second section (218, 318, 418,518, 618, 718, 818, 918, 1018) having a second diameter that is forced to deflect in response to loads within a second load range, the first diameter being greater than the second diameter and the second load range being greater in magnitude than the first load range.

14. The elevator system (100) of claim 12, wherein the plurality of rollers (202, 203, 204, 800, 900, 1000,1100) comprises at least two forward and rearward rollers (202, 203, 1100), the at least two forward and rearward rollers (202, 203, 1100) being aligned with each other at an edge of the base plate (200) to receive opposing surfaces of the guide rail (112) therebetween and limit forward and rearward movement of the elevator car (108).

15. The elevator system (100) of claim 14, wherein the plurality of rollers (202, 203, 204, 800, 900, 1000,1100) includes at least one lateral roller (204, 1100), the at least one lateral roller (204, 1100) being positioned vertically between the forward and rearward rollers (202, 203, 1100) to abuttingly receive an edge of the guide rail (112) and limit lateral movement of the elevator car (108).