WO2019233574A1

WO2019233574A1 - Composite elevator belt and method for making the same

Info

Publication number: WO2019233574A1
Application number: PCT/EP2018/064854
Authority: WO
Inventors: Frank Dudde
Original assignee: Thyssenkrupp Elevator Ag; Thyssenkrupp Ag
Priority date: 2018-06-06
Filing date: 2018-06-06
Publication date: 2019-12-12
Also published as: CN112166083A; WO2019233620A1; CN112166083B; EP3802392A1

Abstract

A composite elevator belt (100) for engaging a sheave includes a load carrier (200) having at least one load carrier strand (211) extending substantially parallel to a longitudinal axis of the load carrier and a resin coating (212) surrounding the at least one load carrier strand and defining a plurality of predetermined, deformable cavities (213) within the resin coating adjacent the at least one strand. When the elevator belt is bent around the sheave, the elevator belt defines a neutral bending zone NZ located within the elevator belt generally coincident with the longitudinal axis, a tension zone TZ radially outward of neutral bending zone, and a compression zone CZ radially inward from the neutral bending zone.

Description

COMPOSITE ELEVATOR BELT AND METHOD FOR MAKING THE SAME

BACKGROUND OF THE INVENTION

Field of the Invention

[0001] The present disclosure is generally directed to composite elevator belts for use in lifting and lowering an elevator car. More particularly, the present disclosure is directed to composite elevator belts having, for example, a load carrier including a central layer and at least one outer layer, each outer layer defining a plurality of deformable pockets to reduce or neutralize tension and compression loads within the composite elevator belts. The present disclosure is also directed to methods for making composite elevator belts.

Description of Related Art

[0002] Elevators for vertically transporting people and goods are an integral part of modem residential and commercial buildings. A typical elevator system includes one or more elevator cars raised and lowered by a hoist system. The hoist system typically includes both driven and idler sheave assemblies over which one or more tension members attached to the elevator car are driven. The elevator car is raised or lowered due to traction between the tension members and drive sheaves. A variety of tension member types, including wire rope, V-belts, flat belts, and chains, may be used, with the sheave assemblies having corresponding running surfaces to transmit tractive force between the tension members and the sheave assemblies.

[0003] A limiting factor in the design of current elevator systems is the minimum bend radius of the tension members. If a tension member is flexed beyond its minimum bend radius, the compressive forces within the tension member may exceed the breaking strength of the tension member material, or may cause the material to buckle and fail. Continuous operation of the tension members below their minimum bend radii can cause fatigue at an increased and unpredictable rate and, under extreme circumstances, may result in a plastic deformation and failure. Thus, the minimum size of the sheaves useable in an elevator system is governed by the minimum bend radius of the tension members.

[0004] For several reasons, sheaves having a smaller diameter allow for more economical elevator system designs. First, the overall component cost of an elevator system can be significantly reduced by using smaller diameter sheaves and sheave assemblies. Second, smaller diameter sheaves reduce the motor torque necessary to drive the elevator system, thereby permitting use of smaller drive motors and allowing for smaller hoistway dimensions. Additionally, decreasing the bend radius of the tension members generally permits easier installation and decreases the spool size of the tension members.

[0005] Accordingly, minimizing the bend radius of elevator tension members and, conversely, increasing tension member flexibility is desirable. Among current tension member designs, composite belts having fiber or wire strands encased in a resin or polymer generally offer the greatest compromise of strength and flexibility. However, such belts must typically have a ratio of the bending diameter to the thickness of the load carrier of greater than 200 (that is, D/t > 200, where“D” is bending diameter and“t” is load carrier thickness) to attain a sufficient fatigue life of the belt. For example, the minimum sheave diameter in a high rise elevator using known composite belts ranges from approximately 600 millimeters to approximately 1000 millimeters due to the stiffness of suitable resin casings. Typically, the resin must have a Young’s modulus of approximately 2 gigapascals (GPa) or greater to adequately support the fibers or strands.

[0006] When a tension member is engaged with a sheave, the tension member is subjected to compression along an outer area in contact with the sheave and tension along an outer area away from the sheave. Frictional tractive force between the tension member and the pulley can impart additional compression to the outer surface of the tension member where the tension member is bent around the sheave. Many materials used to manufacture elevator tension members are significantly stronger in tension than compression. For example, carbon fiber, which is used in many composite belt designs, is typically only 20-70% as strong in compression as it is in tension. Additionally, carbon fiber and many other materials used in strands are brittle when subjected to compression. Therefore, tension members are typically more likely to fail, especially due to fatigue, as a result of internal compression experienced during the engagement with the sheave. Accordingly, the minimum bend radii of existing tension members is governed by internal compression loads due to bending.

SUMMARY OF THE INVENTION

[0007] In view of the foregoing, there exists a need for composite elevator belts which reduce or neutralize internal tension and/or compression loads such that the bending radius of the tension member is reduced while maintaining a high breaking strength. Additionally, there exists a need for methods and apparatuses for forming such composite elevator belts. [000S] Embodiments of the present disclosure are directed to a composite elevator belt for engaging a sheave. The composite elevator belt includes a load carrier having at least one load carrier strand extending substantially parallel to a longitudinal axis of the load carrier and a resin coating surrounding the at least one load carrier strand and defining a plurality of predetermined, deformable cavities within the resin coating adjacent the at least one strand. When the elevator belt is bent around the sheave, the elevator belt defines a neutral bending zone located within the elevator belt generally coincident with the longitudinal axis, a tension zone radially outward of the neutral bending zone, and a compression zone radially inward from the neutral bending zone.

[0009] In some embodiments, when the elevator belt is bent around the sheave, the deformable cavities in the tension zone lengthen longitudinally relative to the longitudinal axis and retract radially relative to the longitudinal axis. When the elevator belt is bent around the sheave, the deformable cavities in the compression zone shorten longitudinally relative to the longitudinal axis and lengthen radially relative to the longitudinal axis.

[0010] In some embodiments, the load carrier includes a plurality of load carrier strands. The plurality of load carrier strands includes a first load carrier strand located in the tension zone and a second load carrier strand located in the compression zone.

[0011] In some embodiments, the first load carrier strand and the second load carrier strand each extend generally parallel to the longitudinal axis.

[0012] In some embodiments, when the elevator belt is bent around the sheave, the first load carrier strand is tensioned in a direction generally parallel to the longitudinal axis and the deformable cavities adjacent the first load carrier strand lengthen longitudinally in a direction generally parallel to the first load carrier strand and shorten radially in the direction generally perpendicular to the first load carrier strand to reposition the first load carrier strand radially closer to the neutral bending zone.

[0013] In some embodiments, when the elevator belt is bent around the sheave, the deformable cavities adjacent the second load carrier strand shorten longitudinally in a direction generally parallel to the first load carrier strand and lengthen radially in the direction generally perpendicular to the first load carrier strand inducing the second load carrier strand to deform into an undulating curve. [0014] In some embodiments, when the elevator belt is bent around the sheave, the undulating curve of the second load carrier strand bends at least partially around the deformed cavities adjacent the second load carrier strand.

[0015] In some embodiments, the plurality of load carrier strands includes a third load carrier strand disposed between the first load carrier strand and the second load carrier strand and located in the neutral bending zone.

[0016] In some embodiments, each of the plurality of cavities encloses one of a gas, a liquid, and a deformable solid.

[0017] In some embodiments, a diameter of each of the plurality of cavities is between one- half and two times the diameter of the at least one load carrier strand.

[0018] In some embodiments, the at least one load carrier strand is non-continuous.

[0019] In some embodiments, the combined Young’s modulus of the resin coating including the plurality of cavities is less than approximately 2 gigapascals.

[0020] In some embodiments, a total volume of the plurality of cavities in the compression zone is substantially equal to one third of a total volume of the resin coating, including the total volume of the plurality of cavities, in the compression zone.

[0021] In some embodiments, a total volume of the plurality of cavities in the tension zone is substantially equal to one third of a total volume of the resin coating, including the total volume of the plurality of cavities, in the tension zone.

[0022] In some embodiments, the composite elevator belt further includes a jacket layer disposed on the load carrier.

[0023] Still other embodiments of the present disclosure are directed to use of a composite elevator belt in an elevator system which includes an elevator shaft having a support frame, an elevator car movable along a vertical travel path defined by the elevator shaft, and a motor arrangement including at least one drive sheave rotatable via the motor arrangement.

[0024] Still other embodiments of the present disclosure are directed to methods of making a composite elevator belt for engaging a sheave. The method includes drawing a load carrier having at least one load carrier strand into a liquid resin bath, surrounding the at least one load carrier strand with a resin coating in the liquid resin bath, and defining a plurality of deformable cavities adjacent the at least one load carrier strand in the resin coating. [0025] In some embodiments, the method further includes drawing the load carrier with the resin coating through a forming and curing die and curing the resin coating into a solidified form to define the plurality of deformable cavities in the resin coating.

[0026] In some embodiments, the method further includes depositing a jacket layer onto the resin coating after solidifying the resin coating into the solidified form.

[0027] In some embodiments, the method further includes intermixing an additive into the liquid resin bath, the additive being one of gas particles, liquid particles, and deformable solid particles. The plurality of deformable cavities are defined by the resin coating solidifying to surround the additive.

[0028] In some embodiments, a volume of the additive intermixed into the liquid resin bath is substantially equal to a volume of the liquid resin in the liquid resin bath.

[0029] In some embodiments, the method further includes intermixing a blowing agent into the liquid resin bath. Curing the resin coating causes the blowing agent to at least partially decompose into gas pockets in the liquid resin surrounding the load carrier strand. The plurality of deformable cavities are defined by the resin coating solidifying around the gas pockets.

[0030] In some embodiments, the method further includes drawing a second load carrier having at least one load carrier strand into a second liquid resin bath, surrounding the at least one load carrier strand of the second load carrier with a resin coating in the second liquid resin bath, and defining a plurality of deformable cavities adjacent the at least one load carrier strand of the second load carrier in the resin coating.

[0031] In some embodiments, the method further includes drawing the first load carrier with the resin coating having the plurality of deformable cavities formed therein into a forming and curing die, drawing the second load carrier with the resin coating having the plurality of deformable cavities formed therein into the forming and curing die, joining the first load carrier with the second load carrier together in the forming and curing die, and curing the resin coatings on the first load carrier and the second load carrier into solidified form in the forming and curing die.

[0032] In some embodiments, the method further includes drawing a third load carrier having at least one load carrier strand into a third liquid resin bath and surrounding the at least one load carrier strand of the third load carrier with a resin coating in the third liquid resin bath. [0033] In some embodiments, the method further includes drawing the first load carrier with the resin coating having the plurality of deformable cavities formed therein into a forming and curing die, drawing the second load carrier with the resin coating having the plurality of deformable cavities formed therein into the forming and curing die, drawing the third load carrier with the resin coating into the forming and curing die interposed between the first load carrier and the second load carrier, joining the first load carrier with the second load carrier together with the third load carrier interposed between the first load carrier and the second load carrier in the forming and curing die, and curing the resin coatings on the first load carrier, the second load carrier, and the third load carrier into solidified form in the forming and curing die.

[0034] Still other embodiments of the present disclosure are directed to an elevator system including an elevator shaft having a support frame, an elevator car movable along a vertical travel path defined by the elevator shaft, a motor arrangement including at least one drive sheave rotatable via the motor arrangement, and at least one composite elevator belt in frictional tractive engagement with and configured to bend around the drive sheave of the motor arrangement. The at least one composite elevator belt includes a load carrier having at least one load carrier strand extending substantially parallel to a longitudinal axis of the load carrier and a resin coating surrounding the at least one load carrier strand and defining a plurality of predetermined, deformable cavities within the resin coating adjacent the at least one strand. When the elevator belt is bent around the drive sheave, the elevator belt defines a neutral bending zone located within the elevator belt generally coincident with the longitudinal axis, a tension zone radially outward of the neutral bending zone, and a compression zone radially inward from the neutral bending zone.

[0035] In some embodiments, when the elevator belt is bent around the drive sheave, the deformable cavities in the tension zone lengthen longitudinally relative to the longitudinal axis and retract radially relative to the longitudinal axis. When the elevator belt is bent around the drive sheave, the deformable cavities in the compression zone shorten longitudinally relative to the longitudinal axis and lengthen radially relative to the longitudinal axis.

[0036] In some embodiments, the load carrier of the composite elevator belt includes a plurality of load carrier strands. The plurality of load carrier strands includes a first load carrier strand located in the tension zone and a second load carrier strand located in the compression zone. [0037] In some embodiments, each of the plurality of cavities of the at least one composite elevator belt encloses one of a gas, a liquid, and a deformable solid.

[0038] In some embodiments a diameter of each cavity in the at least one composite elevator belt is between one-half and two times a diameter of each load carrier strand in the at least on composite elevator belt.

[0039] Further embodiments of the present disclosure will now be described in the following numbered clauses:

[0040] Clause 1. A composite elevator belt for engaging a sheave, the composite elevator belt comprising: a load carrier comprising at least one load carrier strand extending substantially parallel to a longitudinal axis of the load carrier; and a resin coating surrounding the at least one load carrier strand and defining a plurality of predetermined, deformable cavities within the resin coating adjacent the at least one strand; wherein, when the elevator belt is bent around the sheave, the elevator belt defines a neutral bending zone located within the elevator belt generally coincident with the longitudinal axis, a tension zone radially outward of the neutral bending zone, and a compression zone radially inward from the neutral bending zone.

[0041] Clause 2. The composite elevator belt of clause 1, wherein, when the elevator belt is bent around the sheave, the deformable cavities in the tension zone lengthen longitudinally relative to the longitudinal axis and retract radially relative to the longitudinal axis, and wherein, when the elevator belt is bent around the sheave, the deformable cavities in the compression zone shorten longitudinally relative to the longitudinal axis and lengthen radially relative to the longitudinal axis.

[0042] Clause 3. The composite elevator belt of clause 1 or 2, wherein the load carrier comprises a plurality of load carrier strands, the plurality of load carrier strands comprising a first load carrier strand located in the tension zone and a second load carrier strand located in the compression zone.

[0043] Clause 4. The composite elevator belt of any of clauses 1 to 3, wherein the first load carrier strand and the second load carrier strand each extend generally parallel to the longitudinal axis.

[0044] Clause 5. The composite elevator belt of any of clauses 1 to 4, wherein, when the elevator belt is bent around the sheave, the first load carrier strand is tensioned in a direction generally parallel to the longitudinal axis and the deformable cavities adjacent the first load carrier strand lengthen longitudinally in a direction generally parallel to the first load carrier strand and shorten radially in the direction generally perpendicular to the first load carrier strand to reposition the first load carrier strand radially closer to the neutral bending zone.

[0045] Clause 6. The composite elevator belt of any of clauses 1 to 5, wherein, when the elevator belt is bent around the sheave, the deformable cavities adjacent the second load carrier strand shorten longitudinally in a direction generally parallel to the first load carrier strand and lengthen radially in the direction generally perpendicular to the first load carrier strand inducing the second load carrier strand to deform into an undulating curve.

[0046] Clause 7. The composite elevator belt of any of clauses 1 to 6, wherein, when the elevator belt is bent around the sheave, the undulating curve of the second load carrier strand bends at least partially around the deformed cavities adjacent the second load carrier strand.

[0047] Clause 8. The composite elevator belt of any of clauses 1 to 7, wherein the plurality of load carrier strands comprises a third load carrier strand disposed between the first load carrier strand and the second load carrier strand and located in the neutral bending zone.

[0048] Clause 9. The composite elevator belt of any of clauses 1 to 8, wherein each of the plurality of cavities encloses one of a gas, a liquid, and a deformable solid.

[0049] Clause 10. The composite elevator belt of any of clauses 1 to 9, wherein a diameter of each of the plurality of cavities is between one-half and two times the diameter of the at least one load carrier strand.

[0050] Clause 11. The composite elevator belt of any of clauses 1 to 10, wherein the at least one load carrier strand is non-continuous.

[0051] Clause 12. The composite elevator belt of any of clauses 1 to 11, wherein the combined Young’s modulus of the resin coating including the plurality of cavities is less than approximately 2 gigapascals.

[0052] Clause 13. The composite elevator belt of any of clauses 1 to 12, wherein a total volume of the plurality of cavities in the compression zone is substantially equal to one third of a total volume of the resin coating, including the total volume of the plurality of cavities, in the compression zone.

[0053] Clause 14. The composite elevator belt of any of clauses 1 to 13, further comprising a jacket layer disposed on the load carrier. [0054] Clause 15. Use of the composite elevator belt of any of clauses 1 to 14 in an elevator system, the elevator system comprising: an elevator shaft having a support frame; an elevator car movable along a vertical travel path defined by the elevator shaft; and a motor arrangement comprising at least one drive sheave rotatable via the motor arrangement.

[0055] Clause 16. A method of making a composite elevator belt for engaging a sheave, the method comprising: drawing a load carrier comprising at least one load carrier strand into a liquid resin bath; surrounding the at least one load carrier strand with a resin coating in the liquid resin bath; and defining a plurality of deformable cavities adjacent the at least one load carrier strand in the resin coating.

[0056] Clause 17. The method of clause 16, further comprising: drawing the load carrier with the resin coating into a forming and curing die; and curing the resin coating into a solidified form to define the plurality of deformable cavities in the resin coating.

[0057] Clause 18. The method of clause 16 or 17, further comprising depositing a jacket layer onto the resin coating after solidifying the resin coating into the solidified form.

[0058] Clause 19. The method of any of clauses 16 to 18, further comprising intermixing an additive into the liquid resin bath, wherein the additive comprises one of gas particles, liquid particles, and deformable solid particles, and wherein the plurality of deformable cavities are defined by the resin coating solidifying around the additive.

[0059] Clause 20. The method of any of clauses 16 to 19, wherein a volume of the additive intermixed into the liquid resin bath is substantially equal to a volume of the liquid resin in the liquid resin bath.

[0060] Clause 21. The method of any of clauses 16 to 20, further comprising intermixing a blowing agent into the liquid resin bath, wherein curing the resin coating causes the blowing agent to at least partially decompose into gas pockets in the liquid resin surrounding the load carrier strand, and wherein the plurality of deformable cavities are defined by the resin coating solidifying around the gas pockets.

[0061] Clause 22. The method of any of clauses 16 to 21, further comprising: drawing a second load carrier comprising at least one load carrier strand into a second liquid resin bath; surrounding the at least one load carrier strand of the second load carrier with a resin coating in the second liquid resin bath; and defining a plurality of deformable cavities adjacent the at least one load carrier strand of the second load carrier in the resin coating. [0062] Clause 23. The method of any of clauses 16 to 22, further comprising: drawing the first load carrier with the resin coating having the plurality of deformable cavities formed therein into a forming and curing die; drawing the second load carrier with the resin coating having the plurality of deformable cavities formed therein into the forming and curing die; joining the first load carrier with the second load carrier together in the forming and curing die; and curing the resin coatings on the first load carrier and the second load carrier into solidified form in the forming and curing die.

[0063] Clause 24. The method of any of clauses 16 to 23, further comprising: drawing a third load carrier comprising at least one load carrier strand into a third liquid resin bath; and surrounding the at least one load carrier strand of the third load carrier with a resin coating in the third liquid resin bath.

[0064] Clause 25. The method of any of clauses 16 to 24, further comprising: drawing the first load carrier with the resin coating having the plurality of deformable cavities formed therein into a forming and curing die; drawing the second load carrier with the resin coating having the plurality of deformable cavities formed therein into the forming and curing die; drawing the third load carrier with the resin coating into the forming and curing die interposed between the first load carrier and the second load carrier; joining the first load carrier with the second load carrier together with the third load carrier interposed between the first load carrier and the second load carrier in the forming and curing die; and curing the resin coatings on the first load carrier, the second load carrier, and the third load carrier into solidified form in the forming and curing die.

[0065] Clause 26. An elevator system, comprising: an elevator shaft having a support frame; an elevator car movable along a vertical travel path defined by the elevator shaft; a motor arrangement comprising at least one drive sheave rotatable via the motor arrangement; and at least one composite elevator belt in frictional tractive engagement with and configured to bend around the drive sheave of the motor arrangement, the at least one composite elevator belt comprising: a load carrier comprising at least one load carrier strand extending substantially parallel to a longitudinal axis of the load carrier; and a resin coating surrounding the at least one load carrier strand and defining a plurality of predetermined, deformable cavities within the resin coating adjacent the at least one strand; wherein, when the elevator belt is bent around the drive sheave, the elevator belt defines a neutral bending zone located within the elevator belt generally coincident with the longitudinal axis, a tension zone radially outward of the neutral bending zone, and a compression zone radially inward from the neutral bending zone.

[0066] Clause 27. The elevator system of clause 26, wherein, when the elevator belt is bent around any of the drive sheaves or elevator, sheaves, the deformable cavities in the tension zone lengthen longitudinally relative to the longitudinal axis and retract radially relative to the longitudinal axis, and wherein, when the elevator belt is bent around the drive sheave, the deformable cavities in the compression zone shorten longitudinally relative to the longitudinal axis and lengthen radially relative to the longitudinal axis.

[0067] Clause 28. The elevator system of clause 26 or 27, wherein the load carrier of the composite elevator belt comprises a plurality of load carrier strands, and wherein the plurality of load carrier strands comprises a first load carrier strand located in the tension zone and a second load carrier strand located in the compression zone.

[0068] Clause 29. The elevator system of any of causes 26 to 28, wherein each of the plurality of cavities of the at least one composite elevator belt encloses one of a gas, a liquid, and a deformable solid.

[0069] Clause 30. The elevator system of any of clauses 26 to 29, wherein a diameter of each cavity in the at least one composite elevator belt is between one -half and two times a diameter of each load carrier strand in the at least on composite elevator belt.

[0070] These and other features and characteristics of composite elevator belts, methods of making the same, and use of the same in an elevator system will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the disclosure. As used in the specification and claims, the singular forms of“a”,“an”, and“the” include plural referents unless the context clearly dictates otherwise. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] FIG. 1 is a side view of a typical tension member bent about an axis;

[0072] FIG. 2 is a transverse cross-section view through the typical tension member of FIG. i;

[0073] FIG. 3A is a transverse cross-section view of a composite elevator belt according to an embodiment of the present disclosure;

[0074] FIGS. 3B-3D are transverse cross-section views of composite elevator belts according to other embodiments of the present disclosure;

[0075] FIG. 4 is a schematic view of a cross-section of the load carrier of the composite elevator belt of FIG. 3 A in an unloaded state;

[0076] FIG. 5 is a schematic view of the cross-section of the load carrier of the composite elevator belt of FIG. 4 showing a representation of the deformation experienced by the composite elevator belt in a loaded state during use;

[0077] FIG. 6A is a schematic view showing a section of the load carrier of the composite elevator belt of FIG. 4 in a tension zone, prior to bending the composite elevator belt around a sheave;

[0078] FIG. 6B is the schematic view of FIG. 6A illustrating when the composite elevator belt is bent around a sheave;

[0079] FIG. 7A is a schematic view showing a section of the load carrier of the composite elevator belt of FIG. 4 in a compression zone, prior to bending the composite elevator belt around a sheave;

[0080] FIG. 7B is the schematic view of FIG. 7A illustrating when the composite elevator belt is bent around a sheave;

[0081] FIG. 8 is a perspective view of the section of FIG. 7B;

[0082] FIG. 9 is a perspective view of an elevator system utilizing a composite elevator belt according to the present disclosure; and

[0083] FIG. 10 illustrates a manufacturing apparatus for making a composite elevator belt according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

[0084] For purposes of the description hereinafter, the terms“upper”,“lower”,“right”,“left”,

“vertical’’,“horizontal”,“top”,“bottom”,“lateral”,“longitudinal”, and derivatives thereof shall relate to the disclosed apparatus as it is oriented in the figures. However, it is to be understood that the apparatus of the present disclosure may assume alternative variations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific systems and processes illustrated in the attached drawings and described in the following specification are simply exemplary examples of the apparatus disclosed herein. Hence, specific dimensions and other physical characteristics related to the examples disclosed herein are not to be considered as limiting.

[0085] As used herein, the terms“sheave” and“pulley” are used interchangeably to describe a wheel for tractive connection to a tension member of any type. It is to be understood that a “pulley” is encompassed by the recitation of a“sheave”, and vice versa, unless explicitly stated to the contrary.

[0086] As used herein, the terms“substantially” or“approximately”, when used to relate a first numerical value or condition to a second numerical value or condition, means that the first numerical value or condition is within 10 units or within 10% of the second numerical value or condition, as the context dictates and unless explicitly indicated to the contrary. For example, the term“substantially parallel to” means within plus or minus 10° of parallel. Similarly, the term “substantially perpendicular to” means within plus or minus 10° of perpendicular. Similarly, the term“substantially equal in volume” means within 10% of being equal in volume.

[0087] As used herein, the terms“transverse”,“transverse to”, and“transversely to” a given direction mean not parallel to that given direction. Thus, the terms“transverse”,“transverse to”, and“transversely to” a given direction encompass directions perpendicular to, substantially perpendicular to, and otherwise not parallel to the given direction.

[0088] As used herein, the term“diameter” means any straight line segment passing through a center point of a circle, sphere, ellipse, ellipsoid, or other rounded two- or three-dimensional object from one point on the periphery of said object to another point on the periphery of said object. Non-circular and non- spherical objects may have several such diameters of differing length, including a major diameter being the longest straight line segment meeting the aforementioned criteria, and a minor diameter being the shortest straight line segment meeting the aforementioned criteria. [0089] As used herein, the term“associated with”, when used in reference to multiple features or structures, means that the multiple features or structures are in contact with, touching, directly connected to, indirectly connected to, adhered to, or integrally formed with one another.

[0090] Referring to the drawings in which like reference numerals refer to like parts throughout the several views thereof, the present disclosure is generally directed to a composite elevator belt for use in an elevator system to raise and lower an elevator car. It is to be understood, however, that the composite belt described herein may be used in many different applications in which tension members are utilized in traction with sheaves. The present disclosure is also directed to an elevator system utilizing the composite elevator belt. Further, the present disclosure is directed to methods of making the composite elevator belt.

[0091] FIG. 1 illustrates a portion of a typical tension member 1 bent about an axis A, such as a sheave axis, perpendicular to the longitudinal axis L of the tension member. The tension member 1 has a centrally located longitudinal axis L, an inner surface 2 parallel to the longitudinal axis L and radially closest to the axis A, and an outer surface 3 parallel to the longitudinal axis L and radially farthest from the axis A. Generally coincident with the longitudinal axis L is a neutral bending zone NZ. With the tension member 1 bent about the axis A, the tension member 1 deforms such that the outer surface 3, which is radially farthest from the axis A, has a greater arc length than the inner surface 2, which is radially closest to the axis A. As a result of this deformation of the tension member 1, the portion of the tension member 1 between the inner surface 2 and the neutral bending zone NZ compresses, defining a compression zone CZ, and the portion of the tension member 1 between the outer surface 3 and the neutral bending zone NZ stretches, defining a tension zone TZ. The neutral bending zone NZ experiences zero or a negligible stress due to bending the tension member 1 about the axis A. The portion of the tension member 1 defining the compression zone CZ is subject to the compressive stress due to bending, ranging from zero or a negligible compressive stress adjacent the neutral bending zone NZ to a maximum compressive stress at the inner surface 2. Conversely, the portion of the tension member 1 defining the tension zone TZ is subject to the tensile stress due to bending, ranging from zero or a negligible tensile stress adjacent the neutral bending zone NZ to a maximum tensile stress at the outer surface 3. As shown by the arrows in FIG. 1, the compressive stress experienced by the tension member 1 in the compression zone CZ increases substantially linearly from the neutral bending zone NZ to the inner surface 2, and the tensile stress experienced by the tension member 1 in the tension zone TZ increases substantially linearly from the neutral bending zone NZ to the outer surface 3. If the compressive stress experienced in the compression zone CZ reach a critical threshold, the materials of the tension member 1 may experience buckling failure, especially if the materials are brittle. Even below this critical threshold of compressive stress, cyclical compression loading of the tension member 1 may result in fatigue failure.

[0092] FIG. 2 illustrates a transverse cross-section view of the typical tension 1 member of FIG. 1. The tension member 1 generally includes one or more load carrying fibers 4 extending generally parallel to the length of the tension member 1 and encased in a matrix 5. The fibers 4 provide the tensile strength of the tension member 1. The fibers 4 and the matrix 5 may be encased in a jacket 6 adapted to tractively engage the sheave and protect both the sheave and fibers 4 from galling and other wear.

[0093] Referring now to FIGS. 3A-4, a tension member according to one embodiment of the present disclosure is a composite elevator belt 100 including a load carrier 200. In some embodiments, the load carrier 200 is encased in a jacket layer 300. The load carrier 200 provides the tensile strength of the composite elevator belt 100, while the jacket layer 300 is configured for tractive, frictional engagement with a running surface of a sheave, such as an idler sheave or drive sheave. As shown in FIGS. 3A and 4, the composite elevator belt 100 may include a single load carrier 200. However, other embodiments of the composite elevator belt 100, as shown in

FIGS. 3B-3D, may include multiple load carriers 200 arranged in any configuration of rows and columns within the jacket layer 300.

[0094] Each load carrier 200 includes at least one outer layer 210 disposed on a central layer 220. Each of the at least one outer layers 210 may include one or more load carrier strands 211 arranged parallel to the longitudinal axis L of the composite elevator belt 100. In other embodiments, the load carrier strands 211 may be interrupted along the longitudinal axis L, and may or may not overlap one another. In still other embodiments, the load carrier strands 211 may be arranged in multiple layers spaced apart from one another in a direction perpendicular to the longitudinal axis L. In still other embodiments, the load carrier strands 211 may be entangled, discontinuous fibers arranged in a mat or roving. The load carrier strands 211 may be encased in a resin coating 212 which defines a cross-sectional profile of the outer layer 210 and fills any voids between the load carrier strands 211. The one or more load carrier strands 211 may account for between approximately 30% and approximately 60% of the total volume of each outer layer 210. However, the volume ratio of the load carrier strands 211 to the total volume of each outer layer 210 may be adjusted to balance the strength and flexibility of the composite elevator belt 100 for a particular application. Generally, increasing the volume ratio of the load carrier strands 211 to the total volume of each outer layer 210 increases the strength and decreases the flexibility of the composite elevator belt 100, while decreasing the volume ratio of the load carrier strands 211 to the total volume of each outer layer 210 decreases the strength and increases the flexibility of the composite elevator belt 100.

[0095] The central layer 220 may include one or more load carrier strands 221 arranged parallel to and continuous along the longitudinal axis L of the composite elevator belt 100. In other embodiments, the load carrier strands 221 may be interrupted along the longitudinal axis L, and may or may not overlap one another. In still other embodiments, the load carrier strands 221 may be arranged in multiple layers spaced apart from one another in a direction perpendicular to the longitudinal axis L. In still other embodiments, the load carrier strands 221 may be entangled, discontinuous fibers arranged in a mat or roving. The one or more load carrier strands 221 may be encased in a resin coating 222, which defines a cross-sectional profile of the central layer 220 and fills any voids between the load carrier strands 221. The resin coating 222 may be substantially free of any voids or impurities except for those unintentionally introduced during the manufacturing of the central layer 220. The one or more load carrier strands 221 may account for between approximately 60% and approximately 80% of the total volume of the central layer 220. However, the volume ratio of the load carrier strands 221 to the total volume of the central layer 220 may be adjusted to balance the strength and flexibility of the composite elevator belt 100 for a particular application. Generally, increasing the volume ratio of the load carrier strands 221 to the total volume of the central layer 220 increases the strength and decreases the flexibility of the composite elevator belt 100, while decreasing the volume ratio of the load carrier strands 221 to the total volume of the central layer 220 decreases the strength and increases the flexibility of the composite elevator belt 100.

[0096] As the at least one outer layer 210 may occupy either the compression zone CZ or the tension zone TZ of the composite elevator belt 100, the at least one outer layer 210 may be subject to greater loads due to bending than the central layer 220, which may be generally coincident with the neutral bending zone NZ. As such, the ratio of the volume of the load carrier strands 211 of each outer layer 210 to the total volume of that outer layer 210 may be less than the ratio of the volume of the load carrier strands 221 of the central layer 220 to the total volume of the central layer 220.

[0097] The resin coating 212 of each outer layer 210 defines a plurality of deformable cavities 213 interspersed throughout. The plurality of deformable cavities 213 are positioned adjacent to the load carrier strands 211, meaning each of the cavities 213 is spaced apart from the load carrier strands 211, in any direction from the longitudinal axis L, within the resin coating 212. Each of the plurality of cavities 213 encloses a material, which may be a solid, a liquid, or a gas, having a greater deformability than the deformability of the surrounding resin coating 212. The plurality of cavities 213 may account for approximately one third of the total volume of the resin coating 212, although the ratio of the volume of the cavities 213 to the total volume of the resin coating 212 may be adjusted to attain various levels of stress reduction in the composite elevator belt 100, as will be described in detail below with reference to FIG. 5. Each of the plurality of cavities 213 is generally spherical, ovoidal, or ellipsoidal in shape, having a first axis B_x parallel to the longitudinal axis L of the composite elevator belt 100 and a second axis B_Y radially perpendicular to the longitudinal axis L of the composite elevator belt 100. The cavities 213 are not limited to round shapes, and polygonal shapes of the cavities 213 are also considered. Further, the shape of the cavities 213 may be dictated by the method of production of the resin coating 212, as will be described in greater detail below. Additionally, the exact spacing and location of each deformable cavity 213 within the resin coating 212 may be a product of inherent variability in the manufacturing process during which the cavities 213 are defined. However, many properties of the cavities 213 may be predetermined despite variabilities in the manufacturing process. For example, the size of the cavities 213 and the ratio of the total volume of the cavities 213 per unit volume of the resin coating 212 may be predetermined and controlled throughout the manufacturing process. As such, the plurality of deformable cavities 213 may be differentiated from unintentionally occurring voids and/or discontinuities that would naturally occur in the resin coating 212. For this reason, the plurality of cavities 213 may be referred to as being predetermined or predefined. [0098] As shown in FIGS. 5-8, each of the plurality of cavities 213 in the at least one outer layer 210 is configured to deform when the composite elevator belt 100 is bent about an axis A perpendicular to the longitudinal axis L of the composite elevator belt 100. As the composite elevator belt 100 bends around the axis A, the tension zone TZ of the composite elevator belt 100 lengthens relative to the compression zone CZ, causing the cavities 213 in the tension zone TZ and the compression zone CZ to deform in different orientations. In FIG. 5, the plurality of cavities 213 are shown in exaggerated size to more clearly indicate the deformation of the cavities 213.

[0099] Each cavity 213 in the compression zone CZ of the composite elevator belt 100 deforms by retracting or shortening along its first axis B_x and lengthening or extending along its second axis B_Y. Deformation of the cavities 213 reduces or neutralizes the compression loads experienced by the load carrier strands 211 in the compression zone CZ by allowing the load carrier

strands 211 to reposition within the outer layer 210 to a state of reduced stress. The lengthening of each cavity 213 along its second axis B_Y exerts a normal force F_N on the load carrier strands 211 in a radial direction perpendicular to the longitudinal axis L. The normal forces F_N exerted by the cavities 213 on opposite sides of the load carrier strands 211 counteract or neutralize the compressive stress experienced by the load carrier strands 211 due to bending the composite elevator belt 100 about the axis A. More specifically, the normal forces F_N exerted by the

cavities 213 induce the load carrier strands 211 into an undulating curve bending at least partially around the deformed cavities 213. Because an undulating curve inherently has a greater length than a similarly situated smooth curve, inducing the load carrier strands 211 into the undulating curve increases the length of each load carrier strand 211 in the compression zone CZ. The load carrier strands 211 may stretch to attain the increased length of the undulating curve in the compression zone CZ, thus subjecting the load carrier strands 211 to tensile stress which counteracts, and preferably exceeds, the compressive stress due to bending about the axis A. Reduction or elimination of the of the compressive stress on the load carrier strands 211 in the compression zone CZ allows the composite elevator belt 100 to attain a tighter bend radius without exceeding the maximum allowable internal compression. Additionally, replacement of the compressive stress in the load carrier strands 211 with tensile stress eliminates the risk of localized buckling failure and, as the materials used in the load carrier strands 211 are generally much stronger in tension than compression, the load carrier strands 211 may be expected to exhibit a longer service and fatigue life.

[00100] In contrast to the cavities 213 in the compression zone CZ, the cavities 213 in the tension zone TZ deform by lengthening or extending along their first axes B_x and retracting or shortening along their second axes B_Y as the composite elevator belt 100 bends about the axis A. Retraction of the cavities 213 along their second axes B_Y decreases the radial thickness of the resin coating 212 in the tension zone TZ, thereby shifting the load carrier strands 211 in the tension zone TZ closer to the neutral bending zone NZ. By moving closer to the neutral bending zone NZ, the tensile stress experienced by the load carrier strands 211 in the tension zone TZ is reduced. Consequently, the service and fatigue life of the load carrier strands 211 in the tension zone TZ is increased.

[00101] The deformation of the cavities 213 is shown in greater detail in FIGS. 6A-7B, in which the cavities 213 are shown diagrammatically as rectangles to more clearly illustrate the deformation of the cavities 213. FIG. 6A shows a schematic view of a section of the outer layer 210 in the tension zone TZ before the composite elevator belt 100 is bent around the axis A (not shown). FIG. 7A shows a schematic view of a section of the outer layer 210 in the compression zone CZ before the composite elevator belt 100 is bent around the axis A (not shown). As is apparent from FIGS. 6A and 7A, the arrangement of the outer layers 210 in the tension

zone TZ and compression zone CZ is substantially the same in an unbent state of the composite elevator belt 100, except for variance in the location of the cavities 213. This variance in the location of the cavities 213 is unintentional, although it is expected due to the manufacturing process which will be described in greater detail below with reference to FIG. 10.

[00102] FIG. 6B shows the same section of the load carrier 200 as shown in FIG. 6 A, but when the composite elevator belt 100 is bent around the axis A (not shown) such that the depicted belt section is in the tension zone TZ. As explained above, the cavities 213 in the tension zone TZ lengthen along their respective first axes B_x and shorten along their respective second axes B_Y due to a tension force F_T generated by bending the composite elevator belt 100. Shortening of the cavities 213 along their second axes B_Y causes the surrounding resin coating 212 to decrease in thickness perpendicular to the load carrier strands 211. [00103] FIGS. 7B and 8 shows the same section of the load carrier 200 as shown in FIG. 7A, but when the composite elevator belt 100 is bent around the axis A (not shown) such that the depicted belt section is in the compression zone CZ. As explained above, the cavities 213 in the compression zone CZ shorten along their respective first axes B_x and lengthen along their respective second axes B_Y due to a compression force F_c generated by bending the composite elevator belt 100. Lengthening of each cavity 213 along its second axis B_Y exerts a normal force F_N parallel to the second axis B_Y which displaces adjacent load carrier strands 211 in the direction of the second axis B_Y. Deformation of the plurality of cavities 213 exerting normal forces F_N at several locations along the length and around the perimeter of each load carrier strand 211 induces the load carrier strands 211 into an undulating curve. FIG. 8, showing the same section of the load carrier 200 as shown in FIG. 7B with the composite elevator belt 100 bent about the axis A (not shown), illustrates the deformation of the cavities 213 from their undeformed, substantially spherical state to their deformed oblate or partially flattened state. Additionally, FIG. 8 illustrates that the cavities 213 may be interspersed in any location between the load carrier strands 211, such that deformation of the cavities 213 exerts normal forces F_N in all radial directions of the load carrier strands 211. As such, the undulating curve assumed by each load carrier strand 211 may curve in three dimensions.

[00104] Referring now to FIG. 9, other embodiments of the present disclosure are directed to an elevator system 1000 utilizing at least one composite elevator belt 100 described with reference to FIGS. 1-8. The elevator system 1000 may include an elevator car 700 and counterweight (not shown) movable along a vertical travel path defined by an elevator shaft 800 using a plurality of composite elevator belts 100 that raise and/or lower the elevator car 700. In the embodiment shown in FIG. 9, the elevator system 1000 includes four composite elevator belts 100 configured to move the elevator car 700 and a counterweight within the elevator shaft 800. Each end of each composite elevator belt 100 may be held in a separate end termination 900 affixed to a stationary or movable component of the elevator system 1000, such as a support frame 1100, the elevator car 700, or any other load supporting component of the elevator system 1000. The composite elevator belts 100 may be routed around any number of elevator sheaves 400 to alter the direction of the tension force applied by the composite elevator belts 100 on the elevator car 700 and the counterweight. The elevator sheaves 400 may be attached to any portion of the elevator system 1000 including the support frame 1100, the elevator car 700, the counterweight, and/or a floor, a ceiling, or a wall of the hoistway to redirect the pulling force of the composite elevator belts 100 according to the design of the elevator system 1000. In some embodiments, the elevator system 1000 may utilize a one-to-one roping arrangement in which no elevator sheaves 400 are present.

[00105] The composite elevator belts 100 are further routed around drive sheaves 1210 rotatable by at least one motor arrangement 1200. The drive sheaves 1210 fractionally engage the composite elevator belts 100 between opposing ends of the composite elevator belts 100 such that rotation of the drive sheaves 1210 increases or decreases the length of the composite elevator

belts 100 between a first end the of the composite elevator belt 100 and the motor arrangement 1200. Rotation of the drive sheaves 1210 thus causes the elevator car 700 to raise or lower depending on the direction of rotation of the drive sheaves 1210 and the arrangement of the counterweight, end terminations 900, and elevator sheaves 400.

[00106] As may be appreciated from the elevator system 1000 of FIG. 9, either side of the composite elevator belt 100 may be in tension or compression at different locations along the composite elevator belt 100, depending on the arrangement of the drive sheaves 1210 and the elevator sheaves 400. As such, each of the outer layers 210 may define the tension zone TZ at a first location along the longitudinal axis L of the composite elevator belt 100 and the compression zone CZ at a second location along the longitudinal axis L of the composite elevator belt 100. Further, any section of one of the outer layers 210 may define the tension zone TZ with respect to one of the drive sheaves 1210 or one of the elevator sheaves 400, and the same section of one of the outer layers 210 may define the compression zone TZ with respect to another one of the drive sheaves 2100 or another one of the elevator sheaves 400.

[00107] Having described the structure and function of the composite elevator belt 100, one skilled in the art will appreciate that a variety of materials may lend themselves to use for the various components thereof. Examples of suitable materials are generally described below and are further discussed in U.S. Patent Application Serial No. 13/092,391, published as U.S. Patent Application Publication No. 2011/0259677, the entirety of which is incorporated by reference herein. Materials may be selected for their advantageous mechanical properties as well as for their compatibility with manufacturing methods suitable for making the composite elevator belt

100.

[00108] The load carrier strands 211, 221 of the at least one outer layer 210 and the central layer 220 may be made from a variety of natural and synthetic materials which are flexible yet exhibit a high breaking strength. Suitable materials for the load carrier strands 211, 221 thus include glass fiber, aramid fiber, carbon fiber, nylon fiber, basalt fiber, metallic cable, and/or combinations thereof. Some methods of manufacturing the composite elevator belt 100 may utilize inductive heating of the load carrier strands 211, 221, making it advantageous that the material of the load carrier strands 211, 221 is electrically conductive. The load carrier strands 211, 221 may each have a diameter of, for example, between 0.4 pm and 1.2 pm, such as 0.7 pm.

[00109] The resin coating 212, 222 may be made of a polymer matrix material, such as a curable epoxy resin, suitable for deposition on the load carrier strands 211, 221 and flexible when cured. However, alternative resin types may also be utilized. The resin coating 212, 222 may include additives such as fire retardants and release agent to improve the functionality and/or the manufacturing process of the resin coating 212, 222. The material of the resin coating 212, 222 may be selected based on its curing properties, such as the curing rate and the responsiveness of the curing rate to heat. Additionally, the material of the resin coating 212 of the outer layers 210 may be selected for its intermixibility with additives used to form the plurality of cavities 213, as will be described in greater detail below. The material of the resin coating 212 of the outer layers 210 may also be selected to reduce stiffness. In particular, the inclusion of the plurality of cavities 213 in the resin coating 212 may allow for the use of material having a Young’s modulus of less than approximately 2 gigapascal (approximately 290,000 pounds per square inch). That is, the combined Young’s modulus of the resin coating 212, taking into account the plurality of cavities 213 and any additives contained therein, may have an overall Young’s modulus of approximately 2 gigpascal.

[00110] As briefly described above, the material enclosed by each of the plurality of cavities 213 may be any of a solid, a liquid, or a gas. The operative physical property of the material is that the material permits deformation of the associated cavity 213 under tension and compression loading of the composite elevator belt 100. In some embodiments, the material enclosed by each of the cavities 213 may be a gas pocket produced by a blowing agent activated during manufacturing of the resin coating 212 of the outer layer 210. For example, a chemical blowing agent such as azodicarbonamide may be heated during manufacturing of the resin coating 212 to decompose the azodicarbonamide into gases which become trapped in the resin coating 212 as the resin coating 212 cures, defining the cavities 213 around discrete gas pockets created by the azodicarbonamide. In other embodiments, the material enclosed by each of the cavities 213 may be a deformable solid. In still other embodiments, the material enclosed by each of the cavities 213 may be a pocket of liquid.

[00111] Some of the plurality of cavities 213 may enclose a different material than other of the plurality of cavities 213. In embodiments of the composite elevator belt 100 having more than one outer layer 210, each outer layer 210 may utilize the same or a different material in the cavities 213. Each of the plurality of cavities 213 may have a diameter or outer dimension of, for example, between one-half and twice the diameter of the load carrier strands 211 in the associated outer layer 210.

[00112] The jacket layer 300 may be made of a polymer material selected for flexibility and to promote friction with the sheaves 400 and drive sheaves 1200 of the elevator system 1000. Additionally, the material of the jacket layer 300 may be selected for wear resistance of the jacket layer 300 and/or to prevent galling and other damage to the sheaves 400 and drive sheaves 1200. Suitable materials for the jacket layer 300 thus include curable resins such as urethanes, in particular thermoplastic polyurethane (TPU). The material of the jacket layer 300 may be softer than the material of the load carrier 200 by, for example, a factor of ten.

[00113] Other embodiments of the present disclosure are directed to a method of manufacturing the composite elevator belt 100 described above with reference to FIGS. 1-8. Referring now to FIG. 10, an apparatus 2000 at least partially forms each of the at least one outer layers 210 and the central layer 220 individually before the at least one outer layer 210 and the central layer 220 are joined in a final forming stage. As shown in FIG. 10, the apparatus 2000 includes a first roving coil rack 2100a associated with the central layer 220, a second roving coil rack 2100b associated with a first of the outer layers 210, and a third roving coil rack 2100c associated with a second of the outer layers 210. The roving coil racks 2100a-2100c hold the load carrier strands 211, 221 for the outer layers 210 and central layer 220, respectively. A first injection chamber 2200a associated with the central layer 220 and the first roving coil rack 2100a contains a bath of liquid resin for forming the resin coating 222 of the central layer 220. The load carrier strands 221 of the central layer 220 are pulled from the first roving coil rack 2100a and through the first injection chamber 2200a to impregnate the load carrier strands 221 with liquid resin. Similarly, second and third injection chambers 2200b, 2200c associated with the outer layers 220 and the second and third roving coil racks 2100b, 2100c each contain a bath of liquid resin for forming the resin coating 212 of the outer layers 210. The load carrier strands 211 of the two outer layers 210 are pulled from the second and third roving coil racks 2100b, 2100c and through the second and third injection chambers 2200b, 2200c, respectively, to impregnate the load carrier strands 211 with liquid resin.

[00114] The liquid resin in the second and third injection chambers 2200b, 2200c may be intermixed with an additive suitable for forming the plurality of cavities 213 in the resin coating 212. In some embodiments, the additive may be a blowing agent, such as azodicarbonamide, which decomposes into gas during the subsequent curing of the liquid resin. In other embodiments, the additive may be solid particles, liquid particles, or gas particles. The amount or volume of the chosen additive intermixed with the liquid resin may be governed to control the total volume of the cavities 213 ultimately defined in the finished resin coating 212. Measures may be undertaken to ensure that the additive is homogenously intermixed with the liquid resin so that the cavities 213 are subsequently defined having substantially uniform spacing in the finished resin coating 212. In some embodiments, the load carrier strands 211, 221 may be coated with an additive, such as a blowing agent, prior to being pulled into the injection

chambers 2200a, 2200b, 2200c, alternatively or in addition to the additive intermixed with the liquid resin.

[00115] After the load carrier strands 211, 221 of the outer layers 210 and the central layer 220 are impregnated with liquid resin, the load carrier strands 211, 221 are pulled out of the injection chambers 2200a-2200c and into a forming and curing die 2300 where the outer layer 210 and central layer 220 are joined together. When entering the forming and curing die 2300, the liquid resin impregnating the load carrier strands 211, 221 remains in an at least partially liquid phase to facilitate adhesion of the outer layers 210 to the central layer 220. Within the forming and curing die 2300, final shaping of the outer layers 210 and the central layer 220 is performed, and the liquid resin impregnating the load carrier strands 211, 221 is cured to form the resin coatings 212, 222 of the outer layers 210 and central layer 220. Curing of the resin coatings 212, 222 may be achieved, for example, by induction heating of the load carrier strands 211, 221 and/or the liquid resin.

[00116] In embodiments of the composite elevator belt 100 in which a blowing agent is intermixed with the liquid resin of the outer layers 210, the forming and curing die 2300 may also provide heat to decompose the blowing agent prior to or concurrently with the curing of the resin coating 212 of the outer layers 210. Decomposition of the blowing agent forms gas pockets around which the cavities 213 of the resin coating 212 are defined as the resin coating 212 cures. Similarly, in embodiments of the composite elevator belt 100 in which solid particles and/or liquid particles are intermixed with the liquid resin of the outer layers 210, the resin coating 212 cures around the liquid particles and/or solid particles to define the cavities 213.

[00117] After curing is completed in the forming and curing die 2300, the load carrier 200, now including all of the outer layers 210 and the central layer 220 joined together, may optionally be pulled through a jacket extruder 2400 which deposits the jacket layer 300 onto external surfaces of the load carrier 100. The composite elevator belt 100 exits the jacket extruder 2400 fully formed.

[00118] A tractor 2500 located downstream of the jacket extruder 2400 and/or the forming and curing dies 2300 applies a pulling force to unwind the load carrier strands 211, 221 from the roving coil racks 2100a-2100c and pull the load carrier strands 211, 221 through the injection chambers 2200a-2200c, the forming and curing die 2300, and, optionally, the jacket extruder 2400. The finished composite elevator belt 100 is then wound into a spool by a spooler 2600.

[00119] Utilizing the apparatus 2000 described above, a method for making a composite elevator belt 100 includes partially forming the at least one outer layer 210 of the load carrier 100 by impregnating the load carrier strands 211 of the at least one outer layer 210 with liquid resin in the second and third injection chambers 2100b, 2100c. The liquid resin in the second and third injection chambers 2100b, 2100c may be intermixed with an additive selected from a group consisting of deformable materials and blowing agents. The central layer 220 of the load carrier 100 may be formed in substantially the same manner as the outer layers 210, namely by impregnating the load carrier strands 221 of the central layer 220 with liquid resin in the first injection chamber 2100a. The outer layers 210 and the central layer 220 may then be pulled from the forming and curing die 2300 to join the outer layers 210 to the central layer 220 and cure the liquid resin of the outer layers 210 and the central layer 220. Curing the liquid resin of the outer layers 210 forms a solid resin coating defining the plurality of cavities 213 around the additive intermixed with the liquid resin.

[00120] While the apparatus 2000 and method described above provide one embodiment for manufacturing the composite elevator belt 100, variations may be made to suit the requirements of a particular application. For example, the central layer 220, which, in the present embodiment, lacks the plurality of cavities 213 present in the outer layers 210, may be at least partially formed using a different process than the outer layers 210, or the central layer 220 may be pre-manufactured and joined to the partially- formed outer layers 210 in the forming and curing

die 2300. In other embodiments, the central layer 220 may be made similarly to the outer layers 210 such that cavities 213 are formed in the central layer 220 in addition to the outer layers 210. In still other embodiments, additional tooling may be added to the apparatus 2000 to perform additional forming operations to the composite elevator belt 100, or to add further layers to the composite elevator belt 100. In still other embodiments, the load carrier 200 may include an outer layer 210 on only one side of the central layer 220, or the load carrier 200 may include multiple outer layers 210 stacked on and joined with each other on any side or sides of central layer 220.

[00121] While several examples of a composite elevator belt for an elevator system, as well as methods for making the same, are shown in the accompanying figures and described in detail hereinabove, other examples will be apparent to and readily made by those skilled in the art without departing from the scope and spirit of the present disclosure. For example, it is to be understood that aspects of the various embodiments described hereinabove may be combined with aspects of other embodiments while still falling within the scope of the present disclosure. Accordingly, the foregoing description is intended to be illustrative rather than restrictive. The assembly of the present disclosure described hereinabove is defined by the appended claims, and all changes to the disclosed assembly that fall within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

WHAT IS CLAIMED IS:

1. A composite elevator belt (100) for engaging a sheave, the composite elevator belt (100) comprising:

a load carrier (200) comprising at least one load carrier strand (211) extending substantially parallel to a longitudinal axis (L) of the load carrier (200); and

a resin coating (212) surrounding the at least one load carrier strand (211) and defining a plurality of predetermined, deformable cavities (213) within the resin coating (212) adjacent the at least one strand (211);

wherein, when the elevator belt (100) is bent around the sheave, the elevator belt (100) defines a neutral bending zone (NZ) located within the elevator belt (100) generally coincident with the longitudinal axis (L), a tension zone (TZ) radially outward of the neutral bending zone (NZ), and a compression zone (CZ) radially inward from the neutral bending zone (NZ).

2. The composite elevator belt (100) of claim 1, wherein, when the elevator belt (100) is bent around the sheave, the deformable cavities (213) in the tension zone (TZ) lengthen longitudinally relative to the longitudinal axis (L) and retract radially relative to the longitudinal axis (L), and

wherein, when the elevator belt (100) is bent around the sheave, the deformable cavities (213) in the compression zone (CZ) shorten longitudinally relative to the longitudinal axis (L) and lengthen radially relative to the longitudinal axis (L).

3. The composite elevator belt (100) of claim 1, wherein the load carrier (200) comprises a plurality of load carrier strands (211), the plurality of load carrier strands (211) comprising a first load carrier strand (211) located in the tension zone (TZ) and a second load carrier strand (211) located in the compression zone (CZ).

4. The composite elevator belt (100) of claim 3, wherein the first load carrier strand (211) and the second load carrier strand (211) each extend generally parallel to the longitudinal axis (L).

5. The composite elevator belt (100) of claim 3, wherein, when the elevator belt (100) is bent around the sheave, the first load carrier strand (211) is tensioned in a direction generally parallel to the longitudinal axis (L) and the deformable cavities (213) adjacent the first load carrier strand (211) lengthen longitudinally in a direction generally parallel to the first load carrier strand (211) and shorten radially in the direction generally perpendicular to the first load carrier strand (211) to reposition the first load carrier strand (211) radially closer to the neutral bending zone (NZ).

6. The composite elevator belt (100) of claim 3, wherein, when the elevator belt (100) is bent around the sheave, the deformable cavities (213) adjacent the second load carrier (211) strand shorten longitudinally in a direction generally parallel to the first load carrier strand (211) and lengthen radially in the direction generally perpendicular to the first load carrier strand (211) inducing the second load carrier strand (211) to deform into an undulating curve.

7. The composite elevator belt (100) of claim 6, wherein, when the elevator belt (100) is bent around the sheave, the undulating curve of the second load carrier strand (211) bends at least partially around the deformed cavities (213) adjacent the second load carrier strand (211).

8. The composite elevator belt (100) of claim 3, wherein the plurality of load carrier strands (211) comprises a third load carrier strand (211) disposed between the first load carrier strand (211) and the second load carrier strand (211) and located in the neutral bending zone (NZ).

9. The composite elevator belt (100) of claim 1, wherein each of the plurality of cavities (213) encloses one of a gas, a liquid, and a deformable solid.

10. The composite elevator belt (100) of claim 1, wherein a diameter of each of the plurality of cavities (213) is between one-half and two times the diameter of the at least one load carrier strand (211).

11. The composite elevator belt (100) of claim 1, wherein the at least one load carrier strand (211) is non-continuous.

12. The composite elevator belt (100) of claim 1, wherein the combined Young’s modulus of the resin coating (212) including the plurality of cavities (213) is less than approximately 2 gigapascals.

13. The composite elevator belt (100) of claim 1, wherein a total volume of the plurality of cavities (213) in the compression zone (CZ) is substantially equal to one third of a total volume of the resin coating (212), including the total volume of the plurality of cavities (213), in the compression zone (CZ).

14. The composite elevator belt (100) of claim 1, further comprising a jacket layer (300) disposed on the load carrier (200).

15. Use of the composite elevator belt (100) of claim 1 in an elevator system (1000), the elevator system (1000) comprising:

an elevator shaft (800) having a support frame (1100);

an elevator car (700) movable along a vertical travel path defined by the elevator shaft (800); and

a motor arrangement (1200) comprising at least one drive sheave (1210) rotatable via the motor arrangement (1200).

16. A method of making a composite elevator belt (100) for engaging a sheave, the method comprising:

drawing a load carrier (200) comprising at least one load carrier strand (211) into a liquid resin bath;

surrounding the at least one load carrier strand (211) with a resin coating (212) in the liquid resin bath; and

defining a plurality of deformable cavities (213) adjacent the at least one load carrier strand (211) in the resin coating (212).

17. The method of claim 16, further comprising:

drawing the load carrier (200) with the resin coating (212) into a forming and curing die (2300); and

curing the resin coating (212) into a solidified form to define the plurality of deformable cavities (213) in the resin coating (212).

18. The method of claim 16, further comprising depositing a jacket layer (300) onto the resin coating (212) after solidifying the resin coating (212) into the solidified form.

19. The method of claim 16, further comprising intermixing an additive into the liquid resin bath,

wherein the additive comprises one of gas particles, liquid particles, and deformable solid particles, and

wherein the plurality of deformable cavities (213) are defined by the resin coating (212) solidifying around the additive.

20. The method of claim 19, wherein a volume of the additive intermixed into the liquid resin bath is substantially equal to a volume of the liquid resin in the liquid resin bath.

21. The method of claim 17, further comprising intermixing a blowing agent into the liquid resin bath,

wherein curing the resin coating (212) causes the blowing agent to at least partially decompose into gas pockets in the liquid resin surrounding the load carrier strand (211), and

wherein the plurality of deformable cavities (213) are defined by the resin coating (212) solidifying around the gas pockets.

22. The method of claim 16, further comprising:

drawing a second load carrier (200) comprising at least one load carrier strand (211) into a second liquid resin bath; surrounding the at least one load carrier strand (211) of the second load carrier (200) with a resin coating (212) in the second liquid resin bath; and

defining a plurality of deformable cavities (213) adjacent the at least one load carrier strand (211) of the second load carrier (200) in the resin coating (212).

23. The method of claim 22, further comprising:

drawing the first load carrier (211) with the resin coating (212) having the plurality of deformable cavities (213) formed therein into a forming and curing die (2300);

drawing the second load carrier (211) with the resin coating (212) having the plurality of deformable cavities (213) formed therein into the forming and curing die (2300);

joining the first load carrier (200) with the second load carrier (200) together in the forming and curing die (2300); and

curing the resin coatings (212) on the first load carrier (200) and the second load carrier (200) into solidified form in the forming and curing die (2300).

24. The method of claim 22, further comprising:

drawing a third load carrier (200) comprising at least one load carrier strand (221) into a third liquid resin bath; and

surrounding the at least one load carrier strand (221) of the third load carrier (200) with a resin coating (222) in the third liquid resin bath.

25. The method of claim 24, further comprising:

drawing the first load carrier (200) with the resin coating (212) having the plurality of deformable cavities (213) formed therein into a forming and curing die (2300);

drawing the second load carrier (200) with the resin coating (212) having the plurality of deformable cavities (213) formed therein into the forming and curing die (2300);

drawing the third load carrier (200) with the resin coating (222) into the forming and curing die (2300) interposed between the first load carrier (200) and the second load carrier (200); joining the first load carrier (200) with the second load carrier (200) together with the third load carrier (200) interposed between the first load carrier (200) and the second load carrier (200) in the forming and curing die; and

curing the resin coatings (212, 222) on the first load carrier (200), the second load carrier (200), and the third load carrier(200) into solidified form in the forming and curing die (2300).