Patent Publication Number: US-2010115740-A1

Title: Passenger conveyor handrail splicing technique

Description:
FIELD OF THE INVENTION 
     This invention generally relates to passenger conveyors. More particularly, this invention relates to making a handrail for a passenger conveyor. 
     DESCRIPTION OF THE RELATED ART 
     Passenger conveyors have proven effective for carrying people between&#39; different levels within a building or across an elongated pathway, for example. Typical arrangements include a handrail that rides over a balustrade and provides a surface for an individual to grab onto for increased confidence, better stability or both, for example. Typical handrail driving arrangements cause the handrail to move in unison with the steps or belt that carry passengers along the path of the conveyor. Typical handrail drive mechanisms rely upon pinching rollers that engage oppositely facing sides of the handrail to generate enough friction to drive the handrail in the desired direction. 
     There are several problems with conventional handrail driving arrangements. The pinching rollers engage the gripping surface side of the handrail, which tends to scratch and cause wear in the gripping surface. Another shortcoming is associated with the need for friction to cause appropriate movement of the handrail on the one hand and the need for a low friction cooperation between the handrail and the balustrade on the other hand. 
     There is a need for an alternative arrangement for driving handrails. One alternative is shown in U.S. Pat. No. 3,749,224, which includes a toothed belt for driving a handrail. While such arrangements can provide an enhancement to the driving of a handrail, they introduce other complexities. 
     For example, traditional handrails are manufactured by taking a length of handrail stock and splicing together two ends to form a belt or loop. Typical splicing techniques have relatively relaxed tolerances and do not require precise placement of the two ends relative to each other during the splicing operation. Most known arrangements include components to take up any slack in a handrail. With the use of a toothed driving wheel or belt and a correspondingly toothed handrail, further refinements must be made during manufacture. For example, it is necessary to establish an appropriate relationship between the teeth on the one end of the belt stock with the teeth on the other end of the belt stop to ensure a consistent tooth pitch even across the spliced portion. An interruption of the pitch along a splice may prevent appropriate cooperation with the drive mechanism eventually used to drive the handrail, for example. 
     This invention provides the ability to splice together ends of handrail stock to form a handrail that is capable of being driven by a profiled drive mechanism, for example. 
     SUMMARY OF THE INVENTION 
     An example device for joining ends of a passenger conveyor handrail stock includes a plurality of mounting members that each have a configuration for cooperating with a portion of a driven surface on the handrail. At least one of the mounting members is moveable relative to the other. A mover selectively moves at least one of the mounting members relative to the other to establish a desired distance between the mounting members that corresponds to a desired spacing between the portions of the driven surface of the handrail before the ends are spliced together. 
     In one example, the mounting members each have at least one tooth that is adapted to cooperate with at least one tooth on the driven surface of the handrail. 
     In one example, the mover is manually controlled to achieve the desired distance. One disclosed example includes a threaded member such that the mover can be infinitely adjustable within a range of movement of the mover. A disclosed example allows for adjusting the relative positions of the portions of the driven surface of the handrail in increments of 0.01 mm. 
     The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of a currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  schematically illustrated selected portions of a passenger conveyor system. 
         FIG. 2  is a perspective illustration of selected features of an example handrail. 
         FIG. 3  schematically illustrates a device for splicing together ends of handrail stock. 
         FIG. 4  schematically illustrates selected portions of the embodiment of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a passenger conveyor  20 . In this example, a plurality of steps  22  carry passengers between landings  24  and  26  at different levels within a building, for example. Although the illustrated conveyor  20  is an escalator, this invention is not limited to any particular style of passenger conveyor. 
     The passenger conveyor  20  includes a handrail  30  that can be grasped by an individual to increase their confidence, comfort or stability, for example, as they are carried by the conveyor  20 . As can be appreciated best from  FIG. 2 , the handrail  30  includes a gripping surface  32  that faces generally upward along the path that passengers are carried by the conveyor  20 . The handrail  30  also includes a driven surface  34  facing generally opposite from the gripping surface  32 . In this example, the driven surface  34  includes a plurality of teeth  36 . As can be appreciated from  FIG. 1 , a drive mechanism  40  includes a toothed belt  42  that cooperates with the teeth  36  on the handrail  30  for propelling the handrail  30  so that it moves in unison with the steps  22 . 
     One example process of making the handrail  30  includes molding an elongated piece of handrail stock that has the teeth  36  formed on the driven surface  34 . Two ends of the stock are then spliced together to form a continuous loop that is useful with the example conveyor  20  of  FIG. 1 . The presence of the teeth  36  requires special considerations for splicing together the ends of the handrail stock to ensure proper cooperation with the drive mechanism  40 . For example, it is desirable to maintain a continuous and consistent pitch of the teeth  36  along the entire driven surface  34  to ensure proper cooperation with the drive mechanism  40 . Undesirable changes in the spacing between the teeth  36  along an area where the ends of the handrail stock are spliced together interferes with proper operation of the handrail in some examples. If the pitch is not precisely controlled along the entire driven surface  34  in some cases, the drive mechanism will not properly mesh with the driven surface such that it cannot drive the handrail  30 . 
       FIG. 3  schematically shows one example device  50  that is useful for splicing together ends of handrail stock and maintaining a desired relationship between the teeth  36  near each end. The example device  50  includes a base  52  that supports a plurality of mounting members  54  and  56 . In this example, the mounting member  54  holds a portion of the handrail stock associated with one end  58  while the mounting member  56  holds another portion associated with an oppositely facing end  58 . The mounting members  54  and  56  maintain the ends  58  relative to each other in a desired alignment and position within a mold  60  in this example. 
     At least one of the mounting members  54  or  56  is moveable relative to the base  52  for adjusting a spacing between the mounting members  54  and  56  and, therefore, a spacing between the ends  58  of the handrail stock. In the illustrated example, both of the mounting members are moveable relative to the base  52  and relative to each other. 
     One mover  62  is associated with the mounting member  54 . The mover  62  includes a handle  64  that allows manual adjustment of the position of the mounting member  54  relative to the base  52 . In this example, the mover  62  includes a threaded rod  66  and a correspondingly threaded follower  68 . As the rod  66  is rotated, the follower  68  tends to move longitudinally along the rod (e.g., to the left or the right in the drawing). The follower  68  is appropriately associated with the mounting member  54  so that the mounting member  54  moves responsive to rotation of the threaded rod  66 . 
     The illustrated example also includes a mover  72  having a handle  74 , threaded rod  76  and follower  78  associated with the mounting member  56 . 
     Using threaded rods in the movers  62  and  72  allows for an infinite amount of adjustment of the position of the mounting members relative to each other within a range of movement provided by the movers  62  ands  72 . The example arrangement allows for adjusting the spacing between the ends  58  of the handrail stock to within a tolerance level of 0.05 mm. It is possible with such an arrangement, for example, to adjust the position of either end  58  relative to the other in increments of approximately 0.01 mm. Such an arrangement allows for precisely positioning the ends of the stock  58  relative to each other to achieve the desired end result of a handrail once the ends  58  are spliced together. 
     Because the example handrail  30  includes a toothed driven surface  34 , it is necessary for an appropriate relationship between the teeth  36  associated with the ends  58  to be established to have a consistent pitch along the entire length of the handrail  30 , for example. The example mounting members  54  and  56 , as best appreciated from  FIG. 4 , include a positioning member  80  having at least one tooth  82  that cooperates with the teeth  36  on the handrail  30 . The position of the teeth  82  relative to each other can be situated to provide a corresponding desired spacing between teeth  36  on or near the ends  58  of the handrail stock. 
     In one example, the mold  60  includes at least one mold half having a toothed configuration for establishing one or more teeth  36  along the spliced portion of the handrail. In another example, the mold  60  does not establish any teeth  36  along the spliced portion. Depending on the particular drive device  40 , it may not be necessary to have one or more teeth  36  along the spliced portion established by the mold  60  provided that the overall relationship between the teeth  36  is accurate enough to ensure proper cooperation with the drive mechanism  40 . 
     In the illustrated example, each positioning member  80  has a plurality of teeth  82  with a pitch corresponding to a pitch of the teeth  36 . 
     The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this invention. The scope of legal protection given to this invention can only be determined by studying the following claims.