Abstract:
A method of preparing one or more cords for a forming process of a belt for suspending and/or driving an elevator car includes arranging a plurality of wires into a one or more cords. The one or more cords are directed in a cord travel direction toward a jacket former. A high pressure airflow is directed at the one or more cords to remove volatile contaminants from the one or more cords in a direction away from the jacket former. A belt for suspending and/or driving an elevator car includes a plurality of wires arranged into one or more cords. The one or more cords have volatile contaminants removed therefrom via a high pressure airflow applied thereto. A jacket substantially retains the one or more cords.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The subject matter disclosed herein relates to elevator systems. More specifically, the subject disclosure relates to tension members for elevator suspension and/or driving. 
         [0002]    Elevator systems utilize ropes or belts operably connected to an elevator car, and routed over one or more sheaves, also known as pulleys, to propel the elevator car along a hoistway. Belts in particular typically include a plurality of wires at least partially within a jacket material. The plurality of wires is often arranged into one or more strands and the strands are then arranged into one or more cords. In an exemplary belt construction, a plurality of cords is typically arranged equally spaced within a jacket in a longitudinal direction. The cords are typically formed of a plurality of outer strands helically wound around a center strand and each strand is made up of a plurality of wires helically wound around a center wire. The belt is constructed by encapsulating one or more of the cords in the polymeric jacket, typically of a material such as polyurethane. One of two methods are most used, either direct extrusion of the jacket over the one or more cords, or application of the jacket to the one or more cords via a mold wheel process. In either process, volatile contaminants on the one or more cords can result in poor adhesion of the jacket to the steel cords and/or result in voids and bubbles in the jacket. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0003]    According to one aspect of the invention, a method of preparing one or more cords for a forming process of a belt for suspending and/or driving an elevator car includes arranging a plurality of wires into a one or more cords. The one or more cords are directed in a cord travel direction toward a jacket former. A high pressure airflow is directed at the one or more cords of to remove volatile contaminants from the one or more cords in a direction away from the jacket former. 
         [0004]    Alternatively in this or other aspects of the invention, the high pressure airflow is at a pressure in the range of about 3-10 bar. 
         [0005]    Alternatively in this or other aspects of the invention, the high pressure airflow is directed at the one or more cords via one or more nozzles. 
         [0006]    Alternatively in this or other aspects of the invention, the one or more nozzles are one or more ribbon nozzles. 
         [0007]    Alternatively in this or other aspects of the invention, the method includes utilizing a vacuum system located downstream of the high pressure airflow to remove contaminants dislodged by the high pressure airflow. 
         [0008]    Alternatively in this or other aspects of the invention, the method includes heating the high pressure airflow and directing the heated high pressure airflow across the one or more cords to improve adhesion of the jacket material to the one or more cords. 
         [0009]    According to another aspect of the invention, a belt for suspending and/or driving an elevator car includes a plurality of wires arranged into one or more cords. The one or more cords have volatile contaminants removed therefrom via a high pressure airflow applied thereto. A jacket substantially retains the one or more cords. 
         [0010]    Alternatively in this or other aspects of the invention, the method includes applying the jacket material to the plurality of cords via extrusion. 
         [0011]    Alternatively in this or other aspects of the invention, the jacket is formed from an elastomeric material. 
         [0012]    According to yet another aspect of the invention, a cleaning apparatus for preparing one or more cords for forming of a belt for suspending and/or driving an elevator car includes a plurality of nozzles to direct a high pressure airflow at one or more cords to remove volatile contaminants from the one or more of cords. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1A  is a schematic of an exemplary elevator system having a 1:1 roping arrangement; 
           [0014]      FIG. 1B  is a schematic of another exemplary elevator system having a 2:1 roping arrangement; 
           [0015]      FIG. 1C  is a schematic of another exemplary elevator system having a cantilevered arrangement; 
           [0016]      FIG. 2  is a cross-sectional view of an exemplary elevator belt; 
           [0017]      FIG. 3  is a cross-sectional view of a cord for an elevator belt; 
           [0018]      FIG. 4  is a schematic of a method of forming an embodiment of an elevator belt; 
           [0019]      FIG. 5  is a schematic of another method of forming an embodiment of an elevator belt; and 
           [0020]      FIG. 6  is a schematic of yet another method of forming an embodiment of an elevator belt. 
       
    
    
       [0021]    The detailed description explains the invention, together with advantages and features, by way of examples with reference to the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0022]    Shown in  FIGS. 1A ,  1 B and  1 C are schematics of exemplary traction elevator systems  10 . Features of the elevator system  10  that are not required for an understanding of the present invention (such as the guide rails, safeties, etc.) are not discussed herein. The elevator system  10  includes an elevator car  12  operatively suspended in a hoistway  14  with one or more belts  16 . The one or more belts  16  interact with one or more sheaves  18  to be routed around various components of the elevator system  10 . The one or more belts  16  could also be connected to a counterweight  22 , which is used to help balance the elevator system  10  and reduce the difference in belt tension on both sides of the traction sheave during operation. Although the exemplary belt  16  shown  FIG. 2  has a generally planar exterior surface, other arrangements are possible. As one example, belts with a grooved arrangement could be used. 
         [0023]    The sheaves  18  each have a diameter  20 , which may be the same or different than the diameters of the other sheaves  18  in the elevator system  10 . At least one of the sheaves  18  could be a traction sheave and driven by a machine  50 . Movement of the traction sheave by the machine  50  drives (through traction) the one or more belts  16  that are routed around the drive sheave. 
         [0024]    At least one of the sheaves  18  could be a diverter, deflector or idler sheave. Diverter, deflector or idler sheaves are not driven by a machine  50 , but help guide the one or more belts  16  around the various components of the elevator system  10 . The shape of the sheave  18  depends on the shape of the belt  16  that it engages. For example, one or more of the sheaves  18  may have a crown (i.e. a convex shape) along its axis of rotation to assist in keeping the one or more belts  16  centered, or in a desired position, along the sheaves  18 . While such a shape may be used with the belt  16  shown in  FIG. 2 , other shapes are possible. As one example, the sheave could have a grooved surface to receive a grooved belt. 
         [0025]    In some embodiments, the elevator system  10  could use two or more belts  16  for suspending and/or driving the elevator car  12 . In addition, the elevator system  10  could have various configurations such that either both sides of the one or more belts  16  engage the one or more sheaves  18  (such as shown in the exemplary elevator systems in  FIGS. 1A ,  1 B or  1 C) or only one side of the one or more belts  16  engages the one or more sheaves  18 . 
         [0026]      FIG. 1A  provides a 1:1 roping arrangement in which the one or more belts  16  terminate at the car  12  and counterweight  22 .  FIGS. 1B and 1C  provide different roping arrangements. Specifically,  FIGS. 1B and 1C  show that the car  12  and/or the counterweight  22  can have one or more sheaves  18  thereon engaging the one or more belts  16  and the one or more belts  16  can terminate elsewhere, typically at a structure within the hoistway  14  (such as for a machine-room-less elevator system) or within the machine room (for elevator systems utilizing a machine room. The number of sheaves  18  used in the arrangement determines the specific roping ratio (e.g. the 2:1 roping ratio shown in  FIGS. 1B and 1C  or a different ratio).  FIG. 1C  also provides a so-called rucksack or cantilevered type elevator. The present invention could be used on elevator systems other than the exemplary types shown in  FIGS. 1A ,  1 B and  1 C. 
         [0027]      FIG. 2  provides a schematic of an exemplary belt construction. Each belt  16  is constructed of one or more cords  24  and a jacket  26 . As seen in  FIG. 2 , the belt  16  has an aspect ratio greater than one (i.e. belt width is greater than belt thickness). 
         [0028]    The belts  16  are constructed to have sufficient flexibility when passing over the one or more sheaves  18  to provide low bending stresses, meet belt life requirements and/or have smooth operation, while also being sufficiently strong to suspend and/or drive the elevator car  12 . 
         [0029]    The jacket  26  could be any suitable material, including a single material, multiple materials, two or more layers using the same or dissimilar materials, and/or a film. In one arrangement, the jacket  26  could be a polymer, such as an elastomer, applied to the cords  24  using, for example, an extrusion or a mold wheel process. In another arrangement, the jacket  26  could be a woven fabric that engages and/or integrates the cords  24 . As an additional arrangement, the jacket  26  could be one or more of the previously mentioned alternatives in combination. 
         [0030]    Referring now to  FIG. 3 , each cord  24  comprises a plurality of wires  28  in a geometrically stable arrangement. Optionally, some or all of these wires  28  could be formed into strands  30 , which are then formed into the cord  24 . The phrase geometrically stable arrangement means that the wires  28  (and if used, strands  30 ) generally remain at their cross sectional positions in the cord  24  and axial movement of the wires  28  (and if used, strands  30 ) relative to each other is reversible in that they return to their positions. 
         [0031]    The jacket  26  can substantially retain the cords  24  therein. The phrase substantially retain means that the jacket  26  has sufficient engagement with the cords  24  such that the cords  24  do not pull out of, detach from, and/or cut through the jacket  26  during the application on the belt  16  of a load that can be encountered during use in an elevator system  10  with, potentially, an additional factor of safety. In other words, the cords  24  remain at their original positions relative to the jacket  26  during use in an elevator system  10 . The jacket  26  could completely envelop the cords  24  (such as shown in  FIG. 2 ), substantially envelop the cords  24 , or at least partially envelop the cords  24 . 
         [0032]    Referring to  FIG. 4 , to encapsulate the plurality of cords  24  in the jacket  26  the plurality of cords  24  are guided into a jacket former  32 , for example, an extruder, mold wheel or other jacket former. The jacket former  32  encapsulates the cords  24  in the jacket  26 . In the case of an extruder, for example, molten material is applied to the cords  24 , which hardens, resulting in the coated steel belt  16 . 
         [0033]    Prior to entering the jacket former  32 , the cords  24  are guided past a plurality of nozzles  34 . The nozzles  34  direct a high pressure airflow  36  against the cords.  24 . In some embodiments the pressure is in the range of about 3-10 bar at the cords  24 . 
         [0034]    The airflow  36  is urged over cords  24  at an injection angle  38  less than 90 degrees relative to a travel direction  40  of the cords  24  into the jacket former  32 . Injecting the airflow at such an injection angle  38  ensures that volatile contaminants expelled from the cords  24  by the airflow  36  are blown upstream, away from the jacket former  32 , as opposed to toward the jacket former  32 . In some embodiments, after airflow  36  is injected over the cords  24  to dislodge the contaminants, the cords  24  pass through or past a vacuum system  40  to remove any remaining contaminants, preventing them from being redeposited on the cords  24 . 
         [0035]    In some embodiments, as shown in  FIG. 5 , the nozzles  34  are each located at specific cords of the plurality of cords  24   a - 24   d.  Further, more than one nozzle  34  is used to direct flow at each cord  24 , for example, four nozzles  34  equally spaced around a circumference of the cord  24 . Alternatively, as shown in  FIG. 6 , the nozzles  34  may be configured as ribbon nozzles  34 , which direct airflow  36  over two or more cords  24 , or all of the cords  24  of the belt  16 . As with the embodiment of  FIG. 5 , several ribbon nozzles  34  may be utilized to direct the airflow  36  at the cords  24 . 
         [0036]    In some embodiments, the airflow  36  is heated prior to entering former  32  to condition the cords  24  and promote better adhesion of the jacket  16  to the cords  24 . The selected temperature depends on the material forming the cords  24  and jacket  26 . For example, in some embodiments the airflow  36  is heated to between 200-500 degrees Celsius to increase a cord temperature to between about 100-200 degrees Celsius prior to the application of jacket  26  to the cords  24 . 
         [0037]    While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.