Patent Description:
For example, one challenge presented by some elevator belts is achieving a desired amount of traction between the belt and a traction sheave that causes movement of the belt and thus the elevator car. Different approaches have been suggested to achieve particular traction characteristics on a surface of an elevator belt. One approach is shown in the <CIT>. In that document, a jacket includes a roughened surface to provide desired friction characteristics.

Other challenges are associated with the techniques used to apply the jacket to the belt. Some such techniques result in features that are believed to be a cause of noise during elevator operation. Adding a jacket layer also adds cost and manufacturing complexities.

<CIT> discloses a belting fabric made up of a plurality of substantially uncrimped parallel warps, a plurality of substantially uncrimped parallel wefts positioned above and below the warps and transverse thereto, the wefts above and below the warps being in non-opposition in the fabric, at least two binders positioned between each of the adjacent warps and interlacing the wefts above and below the warps in alternating sequence with at least one of the binders between each of the adjacent warps interlacing werfts other than those interlaced by another hinder between the same adjacent warps, the intersections of the binders between each of the adjacent warps being located alternately above and below the centerline of the warps, the space between said adjacent warps being greater than the compressed diameter of the individual binders between the adjacent warps and less than twice the compressed diameter of said individual binders between the adjacent warps, the tension of the binders in the fabric holding said hinder intersections in firm contact with the adjacent warps and being of such magnitude that an increase in the hinder tension produced by the extension of the fabric in the direction of the warps beyond the extension produced by the normal working tension will introduce a mutual embedding and crimping of the warps and wefts and a mutual embedding and crimping of the warps and hinder intersections, the binders in the fabric having a modulus at least as great as the modulus of the warps in the fabric.

<CIT> discloses multi-ply vinyl conveyor, elevator, or transmission belting, i.e., belting made of two or more layers of textile material with an interlayer or interlayers and covers of fire-resisting vinyl polymer material. In its multi-ply vinyl conveyor, elevator, or transmission belting, the warp threads of the textile plies consist at least in part of high-tensile, viscose rayon continuous-filament yarn and the weft threads consist at least in part of jute. <CIT> is disclosing the preamble of the independent claims.

<CIT> discloses a belt carcass comprising a ply formed of warp yarns and weft yarns, wherein predominantly each of such yarns is formed of a plurality of composite units of filament and staple fiber components with a respective filament component being twisted with the staple fiber component of each such composite unit, the filament component being of substantially smaller cross-sectional area than the staple fiber component and being twisted therewith so as to predominantly expose the staple fibers in that composite unit.

Embodiments of the invention may solve one or more of the problems of the art, with the solutions set forth in the independent claims and refinements as recited in the dependent claims.

An elongated elevator load bearing according to the invention is disclosed in claim <NUM>.

A method of making an elongated load bearing member according to the invention is disclosed in claim <NUM>.

Particular embodiments of the method may include any of the following optional features, alone or in combination:.

The various features and advantages of the disclosed examples will become apparent to those skilled in the art from the following detailed description.

<FIG> schematically shows selected portions of an example traction elevator system <NUM>. The illustrated example is for discussion purposes only. Features of the elevator system <NUM> that are not required for an understanding of the present invention (e.g. guide rails, safeties, etc.) are not shown or discussed. Those skilled in the art will appreciate that the present invention could be used in a variety of elevator system configurations and not only the specific example shown in this Figure. This example includes an elevator car <NUM> coupled with a counterweight <NUM> by one or more elongated elevator load bearing members <NUM> in a <NUM>:<NUM> roping arrangement. Other roping arrangements, such as <NUM>:<NUM> or greater, are possible. The weight of the elevator car <NUM> and counterweight <NUM> is suspended by the elongated elevator load bearing members <NUM>.

A traction sheave <NUM> A causes desired movement of the elongated elevator load bearing members <NUM> to achieve desired movement and placement of the elevator car <NUM> within the hoistway. The illustrated example elevator system <NUM> includes a deflector pulley 31B as seen in <FIG> that also engages the elongated elevator load bearing members <NUM>. Other examples include one or more idler or diverter pulleys on the car <NUM>, the counterweight <NUM> or both (for example to provide an overslung or underslung roping arrangement) that also engage the elongated elevator load bearing members <NUM>.

<FIG> illustrates an example elongated elevator load bearing member <NUM>. This example includes a plurality of tension elements <NUM>. As can be appreciated from the drawing, the tension elements <NUM> are arranged generally parallel to each other and extend in a longitudinal direction that establishes a length dimension of the elongated elevator load bearing member <NUM>. A plurality of weave fibers <NUM> are woven together with the tension elements <NUM>. In this example, the weave fibers <NUM> and the tension elements <NUM> are woven together into a fabric that maintains the tension elements <NUM> in a desired orientation relative to each other. In other words, the weave fibers <NUM> substantially retain the tension elements <NUM> in position. The phrase "substantially retained" means that the weave fibers <NUM> sufficiently engage the tension elements <NUM> such that the tension elements <NUM> do not pull out of the weave and remain substantially stationary relative to the weave fibers <NUM> in use (e.g., when the elongated elevator load bearing member <NUM> is subject to a load encountered during use in an elevator system <NUM> with, potentially, an additional factor of safety). The weave fibers <NUM> in this example have a length that is transverse to the length or longitudinal direction of the tension elements <NUM>.

The example load bearing member <NUM> includes an exterior, traction surface <NUM> on at least one side of the load bearing member <NUM>. The traction surface <NUM> is established by exposed weave fibers <NUM>. An "exposed" weave fiber <NUM> in most embodiments will not be exposed along its entire length. The weave fibers <NUM> are woven into the woven fabric of the load bearing member <NUM> so that portions of each fiber will be beneath other weave fibers <NUM> or the tension elements <NUM>.

In the illustrated example, all of the weave fibers <NUM> are exposed on the exterior, traction surface <NUM>. In some examples, the layers of the weave or the arrangement of the weave fibers <NUM> leaves at least some of the weave fibers <NUM> covered over by other weave fibers <NUM>. In such examples, only some of the weave fibers are exposed and establish the exterior, traction surface.

The tension elements <NUM> are the primary load bearing structure of the elevator load bearing member <NUM>. In some examples, the weave fibers <NUM> do not support the weight of the elevator car <NUM> or counterweight <NUM>. Nevertheless, the weave fibers <NUM> do form part of the load path. The weave fibers <NUM> directly transmit the traction forces between the traction sheave <NUM> and the elevator load bearing member <NUM> to the tension elements <NUM> because the weave fibers <NUM> are exposed at the traction surface <NUM>.

The weave fibers <NUM> in some examples prevent the tension elements <NUM> from contacting any component that the traction surface <NUM> engages. For example, the tension elements <NUM> will not contact a surface on the traction sheave <NUM> as the load bearing member <NUM> wraps at least partially about the traction sheave <NUM>. The size of the weave fibers <NUM>, the material of the weave fibers <NUM>, the pattern of the weave fibers <NUM> or a combination of these is selected to ensure the desired spacing between the tension elements <NUM> and the traction surface <NUM> so that the tension elements <NUM> are protected from direct engagement with a component such as the traction sheave <NUM>. The weave fibers <NUM> in some examples cover more than <NUM>% of the surface area of the tension elements <NUM> that faces in the same direction as the traction surface <NUM>.

The tension elements <NUM> comprise a first material and the weave fibers <NUM> comprise a second, different material. In the illustrated example, the weave fibers <NUM> have a much smaller thickness or cross-sectional dimension compared to that of the tension elements <NUM>. The tension elements <NUM> are metallic, such as drawn steel, and the weave fibers <NUM> comprise non-metallic materials, such as polymers for example. The illustrated example tension elements <NUM> in <FIG> comprise metal cords each comprising wound wires.

As a result of the weaving process in this example, each tension element <NUM> remains in a generally planar orientation along its length while the weave fibers <NUM> are in various locations along the length of each weave fiber <NUM>. The weave fibers <NUM> are of a lighter weight compared to the tension elements <NUM> and the weave fibers <NUM> are manipulated during the weaving process to conform about the exterior of the tension elements. Each of the weave fibers <NUM> may be partially wrapped over the top (according to the drawing) of one of the tension elements, beneath an adjacent tension element <NUM> and over the top of the next. In some examples, the tension elements <NUM> are held under tension during the weaving process, which keeps the tension elements <NUM> straight along the portion of their length with which the weave fibers <NUM> are being woven together.

In the illustrated example, all of the tension elements <NUM> are aligned with each other in a generally parallel and generally co-planar arrangement. The weave fibers <NUM> maintain that desired alignment while allowing the load bearing member <NUM> to bend around sheaves in an elevator system. The weave fibers <NUM> maintain the desired relative orientations of the tension members <NUM> without requiring any external coating or jacket over the load bearing member <NUM>.

In some examples, the weave fibers <NUM> include or comprise an elastomer material that is useful for establishing the traction surface <NUM>. One example includes establishing weave fibers <NUM> of a desired material and then coating or impregnating the fibers with the elastomer material. Another example includes making each of the weave fibers <NUM> out of a plurality of filaments and including filaments made of the selected elastomer material within each of the weave fibers <NUM>. One example elastomer material comprises a urethane. Thermoplastic polyurethane is used in one example.

In some examples, the weave fibers <NUM> comprise yarn that is treated with a known sizing material. The sizing in some examples enhances the ability to weave the tension elements <NUM> and weave fibers together. The sizing in some examples enhances a wear characteristic of the weave fibers <NUM> such as minimizing fretting or fraying of the weave fibers during use in an elevator system. The sizing in some examples provides a desired traction characteristic on the traction surface <NUM>.

A variety of different weave patterns can be used to weave together the weave fibers <NUM> and the tension elements <NUM>. <FIG> shows one such example pattern of the weave fibers <NUM>. In this example, the weave fibers <NUM> that are exposed on the exterior, traction surface <NUM> are aligned generally parallel to each other and generally perpendicular to the longitudinal direction of the tension elements <NUM>.

<FIG> schematically illustrates another example weave pattern partially expanded to show the relative orientation of the weave fibers <NUM> relative to each other (the completed assembly would have weave fibers <NUM> and tension elements <NUM> much closer together similar to those shown in <FIG>). In this example, some of the weave fibers 34a are arranged generally perpendicular to the longitudinal direction or length of the tension elements <NUM>. Others of the weave fibers 34b are arranged generally parallel to the tension elements <NUM> and generally perpendicular to the weave fibers 34a. As can be appreciated by comparing <FIG>, the example weave pattern of <FIG> will have a slightly different characteristic on the traction surface <NUM> when the weave fibers 34b are included in a position where they are exposed on the traction surface <NUM>. In another example, the weave fibers 34b are maintained only in spaces between the tension elements <NUM> and are not exposed so they do not have an impact on the contour or texture of the traction surface <NUM>.

One feature of the example of <FIG> is that each of the tension elements <NUM> includes a coating <NUM>. In one example, the coating <NUM> is a protective coating to prevent corrosion of the material of the tension elements <NUM>. In another example, the coating <NUM> comprises an adhesive that facilitates the suitable positioning of, or bonding between, the weave fibers <NUM> and the exterior surface of the tension elements <NUM>. Still another example coating <NUM> comprises an elastomer that may be useful for protecting the material of the tension elements <NUM> during use in an elevator system. An elastomer coating <NUM> can also be useful for suitably positioning, or bonding, the weave fibers <NUM> in place with respect to the tension elements <NUM> if for example such a coating <NUM> is heated after the woven fabric is established.

In the example of <FIG>, each tension element <NUM> comprises a plurality of wires formed into strands 32A that are then wound together into a single cord. In that example, each tension element <NUM> comprises a plurality of individual load bearing strands 32A or wires, for example. In the example shown in <FIG>, the tension elements <NUM> are distributed throughout the weave. The tension elements <NUM> in this example may be of the same size and characteristic as the individual wires or strands within a wound cord such as those included in the example of <FIG>. The tension elements <NUM> in an example like <FIG> may also be of a larger size.

One example configuration like that shown in <FIG> includes discreet metal wires as the tension elements <NUM>. In one such example, the metal wires have an outside diameter that is approximately equal to the outside diameter of the weave fibers <NUM>. In another example, the weave fibers <NUM> have a smaller diameter compared to that of the tension elements <NUM>.

The disclosed examples provide a woven fabric as a basis for an elevator load bearing member. They provide the ability to realize an elevator load bearing member having a plurality of tension elements without requiring an application of a secondary or jacket material. Eliminating the requirement for a secondary coating or jacket enhances the economies of some manufacturing processes and eliminates features of such jackets that have come to be recognized as sources of challenges or drawbacks when they are in use in an elevator system.

One feature of the disclosed examples is that using a weave to maintain the tension elements <NUM> in a desired position relative to each other instead of using a jacket provides more damping compared to the viscoelastic behavior present with urethane jackets. Providing more damping by using a weave instead of a jacket can reduce noise levels during elevator system operation.

Claim 1:
An elongated elevator load bearing member (<NUM>) of a traction elevator system (<NUM>), comprising:
a plurality of tension elements (<NUM>) that extend along a length of the load bearing member (<NUM>); and
a plurality of weave fibers (<NUM>) transverse to the tension elements (<NUM>) and woven with the tension elements (<NUM>), the weave fibers (<NUM>) maintaining a desired spacing and alignment of the tension elements (<NUM>) relative to each other, the weave fibers (<NUM>) at least partially covering the tension elements (<NUM>), the tension elements (<NUM>) comprise a first material and the weave fibers (<NUM>) comprise a second, different material, wherein the tension elements (<NUM>) are at least partially coated with an elastomer material
characterized in that the weave fibers (<NUM>) being exposed and establishing an exterior, traction surface (<NUM>) of the load bearing member (<NUM>), in that the tension elements (<NUM>) comprise metal and the weave fibers (<NUM>) are non-metallic.