Abstract:
A step nose is formed having a tread portion and a riser portion, formed initially as a flat strip, the tread portion having a receiving slot formed therein, and the riser portion having a hook formed as part thereof. The tread and riser portions are stretchable with respect to one another so as to enable the hook to interlockingly engage the slot when the tread and riser portions of the flat strip are bent towards one another to thereby form a step nose ready for installation. Machines are further disclosed for forming the flat step nose strip into an assembled state by bending the tread and riser portions and interlocking them together.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of and priority to U.S. Provisional Application Ser. No. 61/164,341, filed Mar. 27, 2009, entitled, “Improved Step Nose System,” the contents of which are incorporated by reference herein in its entirety. 
     
    
     FIELD 
       [0002]    This disclosure relates to stair case systems and particularly to an improved step nose and step nose system mountable on stair step edges. 
       RELATED ART 
       [0003]    Extrusions for application to staircase step noses to enhance visibility and/or aesthetics in theatres and other venues are known. 
       SUMMARY 
       [0004]    The following is a summary description of an illustrative embodiment of an improved step nose system and components thereof. It is provided as a preface to assist those skilled in the art to more rapidly assimilate the detailed design discussion which ensues and is not intended in any way to limit the scope of the claims which are appended hereto in order to particularly point out the invention. 
         [0005]    In an illustrative embodiment, a step nose strip is formed having a tread portion and a riser portion, formed initially as a flat strip. The tread portion has a receiving slot formed therein, and the riser portion has a hook formed as part thereof. The tread and riser portions are stretchable with respect to one another so as to enable the hook to interlockingly engage the slot when the tread and riser portions of the flat strip are bent towards one another so as to form a step nose ready for installation. The system may further include an end cap and a barbed harpoon connector for attaching the end cap to the step nose strip. The harpoon connector is inserted in respective oppositely disposed openings in the end cap and the step nose strip and thereafter firmly locks the two components together. 
         [0006]    Illustrative embodiments are further disclosed of machines for forming the flat step nose strip into an assembled state by bending the tread and riser portions and interlocking them together. In illustrative embodiments, such a machine may comprise a first roller and a plurality of cooperating guides for initially bending the step nose strip and thereafter feeding it to a wheel having a circular flange thereon which cooperates with the first roller to stretch the riser portion of the step nose downwardly and inwardly. A roller or mandrel at the end of the machine is positioned to push the hook portion of the riser portion into the slot, thereby completing assembly. 
         [0007]    Step nose strips formed according to various embodiments have the advantage that they may be bent and interlocked into final shape in the field, an operation which is facilitated by the disclosed bending machines. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a perspective view of a step nose system according to an illustrative embodiment; 
           [0009]      FIG. 2  is a perspective view of the step nose component of the system of  FIG. 1 ; 
           [0010]      FIG. 3  is a cross-section of the step nose component taken at  3 - 3  of  FIG. 2 ; 
           [0011]      FIG. 4  is a cross-section of the step nose component in an assembled state; 
           [0012]      FIG. 5  is a top view of a harpoon connector component of the system of  FIG. 1 ; 
           [0013]      FIGS. 6 and 7  illustrate end cap components of an illustrative embodiment; 
           [0014]      FIG. 8  is an end view of a wireway component of an illustrative embodiment; 
           [0015]      FIG. 9  is a perspective view illustrating a harpoon connector partially inserted into a step nose and adjacent end cap; 
           [0016]      FIG. 10  is a perspective view of the step nose of the illustrative embodiment being bent by hand; 
           [0017]      FIG. 11  is a perspective view illustrating a method of interlocking of the step nose riser and tread portions of a step nose according to an illustrative embodiment; 
           [0018]      FIG. 12  is a perspective view further illustrating the method of interlocking of the step nose riser and tread portions according to an illustrative embodiment; 
           [0019]      FIG. 13  is a perspective view of an illustrative embodiment of a machine capable of bending the tread and nose portions of the step nose of the illustrative embodiment and causing them to interlock; 
           [0020]      FIG. 14  is a side view of the machine of  FIG. 13 ; 
           [0021]      FIG. 15  is an end view of the machine of  FIG. 14 ; 
           [0022]      FIG. 16  is a perspective view illustrating a step nose strip being initially fed into the machine of  FIGS. 13-15 ; 
           [0023]      FIG. 17  is a perspective view illustrating the step nose strip as it progresses into the machine of  FIGS. 13-15 ; 
           [0024]      FIG. 18  is a perspective view illustrating the step nose strip beginning to engage a wheel component of the machine of  FIGS. 13-15 ; 
           [0025]      FIG. 19  is a second perspective view illustrating the step nose strip beginning to engage the wheel component of the machine of  FIGS. 13-15 ; 
           [0026]      FIG. 20  is a perspective view illustrating the step nose strip engaging an end roller of the machine of  FIGS. 13-15 ; and 
           [0027]      FIG. 21  is an enlarged portion of the view of  FIG. 20 . 
           [0028]      FIG. 22  is a first perspective view of an end cap according to an illustrative embodiment; 
           [0029]      FIG. 23  is a second perspective view of an end cap according to an illustrative embodiment; 
           [0030]      FIG. 24  is a perspective view of a machine capable of bending the tread and nose portion of the step nose strip of the illustrative embodiment and causing them to interlock; 
           [0031]      FIG. 25  is an end view of the machine of  FIG. 24 ; 
           [0032]      FIG. 26  is a top view of the machine of  FIG. 24 ; 
           [0033]      FIG. 27  is a perspective view of a step nose strip being fed into the machine of  FIG. 24 ; 
           [0034]      FIG. 28  is an end view illustrating progress of the step nose strip through the machine of  FIG. 24 ; and 
           [0035]      FIG. 29  is an end view illustrating progress of the step nose strip into the assembled state in the machine of  FIG. 24 . 
       
    
    
     DETAILED DESCRIPTION 
       [0036]    An illustrative embodiment of an improved step nose lighting system  11  is illustrated in  FIG. 1 . The system illustrated includes a folding step nose component or extrusion  13 , an end cap  15 , and first and second end cap-connecting harpoons  17 ,  19 . The system further may include a wireway  21  comprising a wireway base  25  and a wireway cover  23 . The wireway base component  25  has an end  65  which meets flush with an end  67  of the end cap  15  and serves to guide and conceal electrical conductors, which pass therethrough. The illustrative system also includes a second end cap  16  shown in  FIG. 6 . 
         [0037]    In one embodiment, shown in  FIG. 2 , the folding step nose component  13  is formed as a generally flat, bendable strip of flexible PVC (polyvinylchloride), also known as vinyl. In one embodiment, a contrasting light reflective strip  27  is co-extruded with the remainder of the step nose  13 , which remainder is of a dark contrasting color such as black. The light reflective strip  27  may, for example, be colored white or off-white. Suitable PVC materials include, but are not limited to, Geon flexible vinyl PVC injection molding material, UL Listed, RoHS, HB UL94, approx. 85 durometer shore A, as well as Geon Flexible Vinyl PVC C8000 Material. 
         [0038]    As shown in the cross-section of  FIG. 3 , the step nose  13  includes a tread portion  29  and a riser portion  31 . A flexible web  30  interconnects the tread and riser portions  29 ,  31  as shown in  FIG. 3 . As illustrated, the tread portion  29  includes three generally rectangular openings or cells  33 ,  35 ,  37  which extend through the entire length of the step nose strip  13 . The riser portion  31  includes two generally rectangular openings or cells  39 ,  41 , which again extend through the entire length of the step nose strip  13 . 
         [0039]    In the embodiment illustrated in  FIG. 3 , the riser portion  31  of the step nose strip  13  may lie at a slight angle to the horizontal as initially formed, but the strip may be characterized as generally flat compared to the assembled state of  FIG. 4 . 
         [0040]    A hook  43  is further formed at the interior end of the riser portion  31 , while a hook receiving slot  45  is formed on the interior end of the tread portion  29 . As may be seen, the slot  45  is defined by a projecting lip  47 . The lip  47  has an inner surface  49 , which projects upwardly at a slight angle to the horizontal. 
         [0041]    The hook  43  and slot  45  are dimensioned such that, as the riser portion  31  is rotated in the direction of the arrow  51  in  FIG. 3 , the hook  43  may be forced into mating relation with the slot  45  as shown in  FIG. 4 . In this position, in the illustrative embodiment, the riser portion  31  lies at an angle θ of eighty degrees (80°) with respect to the horizontally disposed tread portion  29 . Because of the flexible nature of the material, the riser portion  31  may lie at various other installation angles with respect to the tread portion  29  when assembled such as, for example, 90 degrees ( FIG. 1 ) to accommodate various “kickbacks” of staircase designs. Illustrative dimensions of one embodiment in inches are:
       d 1 =0.400 d 4 =0.400 d 6 =1.700 d 2 =2.125 d 5 =0.400 d 7 =1.025
 
where d 1  is a height of the tread portion  29 , d 2  is a width of the tread portion  29 , d 4  and d 5  are the widths of the respective generally rectangular openings  33  and  41 , d 6  is a width of the riser portion  31 , and d 7  is the width of the reflective strip  27 . Such dimensions may of course vary in different embodiments.
       
 
         [0043]    An advantage of step nose constructed according to the illustrative embodiment is that long lengths of flat strips such as shown in  FIGS. 2 and 3  may be readily shipped to an installation location, cut to length, and then bent into the configuration of  FIG. 4  “in the field.” This is a particular advantage where installation is to be done in a foreign country or where stair cases are of non-uniform width, e.g. decreasing in width from top to bottom in a “V-shape.” In other applications, factory cutting and bending to ordered length may suffice. Additionally, seamless lengths may be installed. 
         [0044]    In one embodiment of the system, respective ends of a folding step nose section  13  are finished by attachment of respective right and left end caps  15 ,  16 . As seen for example in  FIGS. 6 ,  7 ,  22  and  23 , the end caps  15 ,  16  contain respective internal cells  233 ,  235 ,  237 ,  239 ,  241 ;  333 ,  335 ,  337 ,  339 ,  341 , which may have the same cross-section as the mating openings  33 ,  35 ,  37 ,  39 ,  41  of the step nose strip  13 . Each end cap  15 ,  16  also has a respective tread portion  243 ;  353  and a respective riser portion  245 ;  355 . 
         [0045]    The end caps  15 ,  16  are preferably attached by respective “harpoon” end cap connectors, e.g.  17 ,  19 , which are inserted in the top end most cells and lower end most cells of the strip  13  and end connectors  15 ,  16 . 
         [0046]    As shown in  FIG. 5 , each harpoon connector, e.g.  17 , has a set  61 ,  63  of barbs or teeth on each end. One set of barbs, e.g.  61 , is designed to bite into the interior wall of an opening in an end cap  15 ,  16 , while the other set of barbs, e.g.  63 , is designed to bite into the interior surface of one of the cells or openings in the step nose  13 . In the illustrated embodiment, each set of barbs, e.g.  61 , includes a number of barbs disposed along a first edge of the connector  17  and an equal number of barbs disposed on the opposite edge of the connector  17 , each respective barb on one edge disposed opposite a corresponding barb on the opposite edge. 
         [0047]    In one embodiment, one harpoon connector  17  attaches the tread portion of an end cap  15  to the tread portion  29  of the step nose  13 , while a second harpoon connector  19  attaches the riser portion  31  of the end cap  15  to the riser portion  31  of the step nose  13 . In this manner, a very secure connection and attachment of the end caps to the step nose  13  is achieved. In the illustrative embodiment, a harpoon connector is inserted into each of the openings  33 ,  41  in step nose  13  and into oppositely disposed openings in each end cap  15 ,  16 . 
         [0048]    As illustrated in  FIG. 9 , the width “W” from tip to tip of oppositely disposed barbs may be just slightly greater than the width of the end cap and step nose-openings into which the harpoon connector  17  is inserted. In this manner, the relatively thin ends of the barbs  61 ,  63  bend backwards to permit insertion and thereafter “bite” into the surface of end cap or step nose strip openings. In one illustrative embodiment, the harpoon connector  17  may be made from 18 gauge cold rolled steel or other metal and may have the following illustrative dimensions in inches ( FIG. 5 ) W=4.75, d 8 =0.125, d 9 =1.130, θ 2 =50 degrees. Various other dimensions may be used of course in various embodiments 
         [0049]    As illustrated in  FIG. 10 , simply bending the step nose  13  of the illustrative embodiment shown in  FIG. 3  by hand to rotate the riser portion  31  towards the tread portion  29  in the direction of arrow  51  results in the back surface  42  of the hook  43  abutting the foot  44  of the receiving slot  45 . In order to cause the hook  43  and slot  45  to mate in interlocking relation, the riser portion  31  must first be stretched downwardly as shown in  FIG. 11  and then moved inwardly as shown in  FIG. 12 . Once the components are positioned as shown in  FIG. 12 , they simply need to be moved vertically with respect to one another to cause the hook  43  and slot  45  to engage or interlock. 
         [0050]    A machine  71  for performing the operations necessary to interlock the tread and riser portions  29 ,  31  in the manner shown in  FIG. 4  is illustrated in  FIGS. 13-15 . This machine  71  includes a first roller  73 , which rotates about a horizontal axis disposed opposite a pair of guide sleeves,  75 ,  77 , each rotatably mounted on respective vertical shafts attached to a first horizontal arm  83 . Rotating horizontal guide sleeves  80 ,  82  are further provided beneath the first roller  173 . 
         [0051]    Adjacent the first roller  73  is mounted a separator wheel  85 , which is mounted to rotate in a horizontal plane about a vertical axis. The separator wheel  85  has a circular flange  87  thereon. Across from the separator wheel  85  are positioned two rollers, a pinch roller  91  and a deflection roller  93 . These rollers or wheels  91 ,  93  each are rotatably mounted on respective vertical shafts  95 ,  97 . In the illustrative embodiment, the axes of these shafts  95 ,  97  are offset slightly such that the deflection roller  93  is inset slightly towards the wheel  85 . The shafts  95 ,  97  are attached to a second horizontal arm  99  of an undercarriage  100 . The wheel  85  is further rotatably mounted to a third arm  101  of the undercarriage  100 , which is in turn rigidly attached to a central post  103  rigidly attached to a flat rectangular base  105 . 
         [0052]    Operation of the machine  71  is illustrated in  FIGS. 16-20 . As may be seen, the tread portion  29  of the initially flat step nose strip  13  is fed into the machine  71  vertically between the first roller  73  and vertical sleeves  75 ,  77 , while the riser portion  31  is fed in horizontally between the first roller  73  and the horizontal sleeves  80 ,  82 , thereby bending the tread  29  and riser  31  toward one another. 
         [0053]    As the step nose  13  is fed manually into the machine  71  and past the first roller  73 , the first roller  73  and the lip  87  of the wheel  85  cooperate to stretch the riser portion  31  downwardly and inwardly as shown in  FIGS. 18 and 19 , thus pushing the hook  43  of the riser portion  31  over and opposite the slot  45  of the tread portion  29 . As shown in  FIG. 20 , the deflection roller  93  completes the interlocking process by pushing the hook  43  into the slot  45  and thereafter releasing.  FIG. 20  also illustrates how the riser portion  31  is sandwiched between the lip  87  and a rim  88  formed on the wheel  85 . 
         [0054]    In another embodiment, the feed mechanism may be automated, for example, by employing an electric motor and drive shaft to drive the large wheel  85 . One such embodiment may be configured to allow an electric drill to drive the large wheel  85 . In some embodiments, teeth may be provided, for example, on the lip  87  and/or on the first wheel  73  to better grip the step nose  13  and assist in feeding it through the machine  71 . 
         [0055]    A second embodiment of a machine  171  for interlocking the tread and riser portions  29 ,  31  is illustrated in  FIGS. 24-29 . This machine  171  includes a first roller  173 , rotatably mounted to a vertical arm  174 , which is rigidly attached to a base platform  184 . The first roller  173  rotates about a horizontal axis and is disposed opposite a pair of guide sleeves,  175 ,  177 , each rotatably mounted on respective vertical shafts  179 ,  181  attached to a mounting block  183 , which is rigidly attached to a base platform  184  by suitable fastening devices. Rotating horizontal guide sleeves  180 ,  182  are further provided beneath the first roller  173 . A third rotatably mounted vertical guide sleeve  176  is positioned on the base platform  184  in front and to the side of the first roller  173 . 
         [0056]    Adjacent to the first roller  173  is mounted a separator wheel  185 , which is mounted to rotate in a horizontal plane about a vertical axis. The wheel  185  has a circular flange  187  thereon. As seen in  FIG. 25 , the flange  187  is positioned above and spaced apart a distance D 1  from a circular plate  190 . Another circular plate  197  is attached to the wheel  185  and has a mounting block  192  attached thereto. A hand crank  194  is attached to the mounting block and is operable to rotate the wheel  185 , flange  187  and plate  190  in unison. 
         [0057]    Across from the wheel  185  is positioned a mandrel  191 . As may be seen in  FIGS. 28 and 29 , the mandrel  191  has a conically shaped portion  195  which diminishes in diameter and meets a cylindrical flange  197  at the top of mandrel  191 . The conical portion  195  forms into a cylindrical bottom section  194  which is rigidly attached to the base  184 . 
         [0058]    Illustrative dimensions of an illustrative machine  171  are shown in the top view of  FIG. 26 . In this embodiment the outside (widest) diameter D 2  of the mandrel  191  is 2.110 inches and its center  199  is spaced at a distance D 3  of 4.062 inches from the center  201  of the flange  187 . The diameter D 4  of the flange  187  and the circular plate  190  in this embodiment is 5.990 inches. The horizontal axis  203  about which the wheel  173  rotates is positioned a distance D 5  of 3.470 inches from the vertical axis  201  about which the wheel  185 , flange  187  and plate  190  rotate. The angle of the conical edge of the mandrel  191  may lie at angle of 12 degrees from the vertical in one embodiment. 
         [0059]    Operation of the machine  171  is illustrated in  FIGS. 27-29 . As may be seen, the tread portion  29  of the initially flat step nose strip  13  is fed into the machine  171  vertically between the first roller  173  and vertical sleeves  175 ,  177 , while the riser portion  31  is fed in horizontally between the first roller  173  and the horizontal sleeves  180 ,  182 , thereby bending the tread  29  and riser  31  toward one another. 
         [0060]    As the step nose  13  is fed into the machine  171  and past the first roller  73 , the riser portion  31  enters the space between the flange  187  and circular plate  190  ( FIG. 28 ), and the hand crank  194  is operated to pull the flat step nose strip  13  through the machine  171 . As shown in  FIG. 28 , the flange  187  is dimensioned to engage the hook  43  and push the hook  43  and adjacent web surface  30  against the mandrel  191 , thereby positioning the hook  43  opposite the receiving slot  45  of the tread portion  29 . As seen in  FIG. 29 , as the step nose strip  13  proceeds further through the mandrel  171  and somewhat further past the mandrel  191  the hook  43  moves into interlocking relation with hook receiving slot  45 . The hand crank  194  is then continuously rotated to interlock the hook  43  and slot  45  along the entire length of the step nose strip  13 . The hand crank mechanism  194  may again be automated, as discussed above with respect to the first embodiment of  FIGS. 13-21 . 
         [0061]    Those skilled in the art will appreciate that various adaptations and modifications of the just described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.