Abstract:
A public access stair assembly for use with a scaffold assembly and methods for assembling or installing such an assembly are disclosed. Advantageously, the stair assembly is connected in-line with the scaffold assembly to create an integrated public access stair system. The system and methods disclosed herein provide numerous benefits including, by way of example and not limitation, quick installation and dismantling.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority under 35 U.S.C. §119(e) to Provisional Patent Application Ser. No. 60/890,234, filed on Feb. 16, 2007, the entire disclosure of which is hereby incorporated by reference, 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates generally to public access stair system and more particularly to a public access stair system for use with a scaffold system. 
       BACKGROUND 
       [0003]    Public access stairs can allow users to access temporary or semi-permanent grandstands, private boxes and other platforms. Scaffold assemblies are generally known and typically include vertical and horizontal members that are connected together. Such assemblies typically permit relatively rapid erection and dismantling. However, attempts to utilize public access stair units in conjunction with scaffolding, have either not been feasible, or at best, difficult to execute. For example, large quantities of on-site fabrication of items such as handrails, thresholds, turnarounds, and the like, have typically been required. 
         [0004]    As such, it would be desirable to provide a public access stair system that allows for rapid installation of stairs onto scaffolding such that problems, including on-site fabrication of components, are reduced substantially or altogether eliminated. 
       SUMMARY 
       [0005]    In accordance with at least one aspect of the present invention, a public access stair assembly for use with a scaffold assembly having horizontal members that are connected to vertical members is disclosed. The public access stair assembly comprises a plurality of stringer support bracket assemblies for connection to a scaffold assembly; a stringer mechanism connected to a plurality of stringer support bracket assemblies; a guard rail assembly having a plurality of guard rail post mechanisms capable of supporting a guard rail mechanism and a guard panel structure, the post mechanisms connected to the plurality of stair stringer support bracket assemblies; and a plurality of stair units that are connected, at least indirectly to, at least one of the plurality of stringer support bracket assemblies, the stair stringer mechanism and the guard rail post mechanisms, the plurality of stair units permitting a user of the public access stair assembly to ascend to an upper end of the stair assembly and/or descend to a lower end of the stair assembly. 
         [0006]    In accordance with another aspect of the present invention, a method of assembling a public access stair system is disclosed, The method includes providing a scaffold assembly that includes a plurality of vertical members that are connected to a plurality of horizontal members; providing a plurality of support bracket assemblies and connecting the plurality of support bracket assemblies to the scaffold assembly; providing a public access stair assembly having a guard rail assembly that includes a plurality of guard rail post mechanisms, the stair assembly further including a plurality of stair units; and connecting the public access stair system to the scaffold assembly using the plurality of support bracket assemblies such that the plurality of post mechanisms are in-line with respect to the plurality of vertical scaffold members. 
         [0007]    In accordance with another aspect of the present invention, a method of assembling a public access stair system is disclosed. The method includes providing a supporting scaffold assembly having a plurality of horizontal scaffold members that are connected to a plurality of vertical scaffold members; providing a plurality of stringer support brackets assemblies; connecting the plurality of stringer support bracket assemblies to the supporting scaffold assembly; providing a plurality of stringer mechanisms having a plurality of stair units secured thereto; connecting and securing the plurality of stringer mechanisms to the plurality of stringer support bracket assemblies; providing a plurality of guard rail post mechanisms; connecting the plurality of guard rail post mechanisms to the plurality of stringer support bracket assemblies; providing a plurality of guard panels; connecting the plurality of guard panels to the plurality of guard rail posts; providing a hand rail or hand rail segment; and connecting the hand rail or hand rail segment to the plurality of guard rail posts and to the plurality of guard panels. 
         [0008]    Various embodiments of the invention, including various embodiments of the assembly and methods are disclosed, contemplated and considered within the scope of the present invention. The inventive assembly and methods provide numerous benefits including, by way of example and not limitation, quick installation and dismantling which results in a reduction of costs (e.g., reduced labor costs). Other benefits will be apparent from the detailed description that follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Embodiments of the invention are disclosed with reference to the accompanying drawings and are for illustrative purposes only. The invention is not limited in its application to the details of construction or the arrangement of the components illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in other various ways. Like reference numerals are used to indicate like components. In the drawings: 
           [0010]      FIG. 1  illustrates a side view of a public access stair system having a stair assembly in accordance with at least some embodiments of the invention, the assembly shown without a handrail assembly supported by an exemplary scaffold assembly; 
           [0011]      FIG. 2  illustrates a side view showing a portion of the inventive public access stair system of  FIG. 1 , enlarged to better illustrate various components of the stair assembly and including a handrail assembly; 
           [0012]      FIG. 3  is an exploded perspective view of a portion of the public access stair system in accordance with at least some embodiments of the invention; 
           [0013]      FIG. 4  is a side view of a portion of the public access stair system taken along line  4 - 4  of  FIG. 2 ; and 
           [0014]      FIG. 5  is a reverse bottom perspective view showing one embodiment of a segment of a public access stair system. 
       
    
    
       [0015]    Various items of equipment, such as fittings, fasteners, etc., have been omitted from the drawings. Those skilled in the art will realize that such conventional equipment can be employed as desired. Additionally, in certain of the drawings, various components of the system or of the assemblies or sub-assemblies may be omitted. In general, those skilled in the art will recognize that any such omissions are by design and are to simplify the drawings and associated description of the invention in its many embodiments. 
       DETAILED DESCRIPTION 
       [0016]    Disclosed herein is a public access stair system that can be used to provide, by way of example, access to temporary or semi-permanent grandstands and private boxes. The access stair system is, advantageously, compatible with scaffolding systems. Advantageously, the inventive system can be used as a means of public access to grandstands and other platforms requiring stairs to accomplish such access. 
         [0017]      FIGS. 1 and 2  illustrate a public access stair system, generally referenced by numeral  20 , in accordance with at least some embodiments of the invention. By way of introduction, it is noted that the drawings essentially illustrate exemplary segments or portions of various embodiments of the invention. In use, additional segments or portions, similar or identical to those shown and described herein, or similar or identical to segments or portions that are provided in accordance with other embodiments of the present invention, are assembled, connected or otherwise provided in mechanical association with other similar or identical segments or portions to assemble a final or complete public access stair assembly system that is suitable for use. The public access stair system  20  includes a public access stair assembly, generally referenced by numeral  22 . The stair assembly  22  is connected to, or more generally can be considered to be in mechanical association with, a scaffold assembly, which is generally referenced by numeral  24 . Accordingly, the public access stair assembly  22  is supported, at least indirectly, by the scaffold assembly  24 . An exemplary scaffolding system contemplated for use in conjunction with the public access stair assembly  22  is the Safway® Systems Scaffold, which is available from ThyssenKrupp Safway, Inc., located in Waukesha, Wis. The inventive stair system is designed to utilize, or work in conjunction with, including the Safway Systems™ Scaffold, such that the scaffold system serves as a public access stair system support structure. However, it is understood that the present invention should not be limited to this or necessarily any particular scaffold system. 
         [0018]    Still referring to  FIGS. 1 and 2 , the scaffold assembly  24  includes horizontal scaffold members  30 , which typically take the form of tubes or tube-like structures, as well as vertical scaffold or post members  32 , which also typically take the form of tubes or tube-like structures. The horizontal and vertical members are connected at predetermined distances to achieve a desired slope. In accordance with at least some embodiments, the scaffolding or scaffold assembly  24  provides for or permits attachment or connection of a horizontal scaffold tube  30  to a vertical scaffold post  32  every  21  inches vertically and this is indicated by Diagram A. In accordance with at least some embodiments using the scaffold system noted above, a horizontal bearer (e.g., a 3-foot SBR3 Safway Systems Scaffold horizontal bearer) can be combined with or connected to the vertical posts (e.g., a Safway Systems Scaffold Vertical Post) to create the necessary slope. The scaffold assembly  24  includes primary bracket or connector mechanisms  34  to connect the horizontal and vertical scaffold members  30  and  32 , respectively. The scaffold assembly  24  further includes additional connector mechanisms  36  (only shown in  FIG. 1 ) and brace assemblies  38  (again only shown in  FIG. 1 ), which typically include a plurality of brace mechanisms, and which are used to connect and support the horizontal and vertical scaffold members  30  and  32 , respectively, over a longer span. More specifically, such additional bracing is typically included to provide for added support and rigidity as needed. The configuration of such bracing can vary (e.g., in size, shape, number of component brace mechanisms, etc.) depending upon a variety of factors associated with the particular end-use application, for example, a required load to be supported over a given span. Those of skill in the art shall recognize that the invention is not limited to the above-mentioned or any particular geometry or connection scheme or format. 
         [0019]    As shown, the public access stair assembly  22  includes a plurality of stringer mechanisms  40 , or stringers, and the stringer mechanisms are connected to and serve, at least in part, to support stair units  42  via stair unit supports  44 . Each stringer  40  is a modular unit that is light weight, and inexpensive to fabricate, transport, and handle. As illustrated specifically in  FIG. 2 , the stair assembly  20  further includes a guard rail assembly  21 . The assembly  21  includes guard rail posts or post mechanisms  46  which are connected to and supported by the stringer mechanisms  40  and the scaffold assembly  24 . The guard rail posts  46  permit secure attachment of each hand rail segment  48  which makes up a handrail  50 . Panels  52  (two of which are shown) are included and secured to, or captured by, the guard rail posts and the hand rail segments  48 . These panels are typically made of wood (e.g., plywood) and can be termed “guard panels” since they can generally serve to provide additional safety for users walking on the stair assembly  22 . The guardrail posts  46  also include one or more plates  47  which allow the attachment of a handrail segment  48 . In the present embodiment, this handrail segment  48  comprises an integral channel  49  that covers, or substantially covers, the top (typically exposed) edge or portion of the plywood panels  52 . The channel(s)  49  have plates  47  on either end which serve to couple the handrail segment such that the handrail  50  is an extended, smooth, and continuous handrail for the system  20 . Here again, those of skill in the art will recognize that variations to the illustrated embodiment, for example, changes to the size, shape and geometry of the assembly components, are contemplated and considered within the scope of the present invention. 
         [0020]      FIG. 3  is an exploded perspective view of one embodiment of the public access stair system  20 . As noted above, the stair system  20  includes stair assembly, generally referenced by bracketed lines and numeral  22 , which is connected to the scaffold assembly, which is generally referenced by bracketed lines and numeral  24 . The stair assembly is again shown to include a stringer mechanism  40  that is connected to the stair unit  42  via supports  44 . The stair assembly further includes a guard rail assembly  21 . The assembly  21  includes guard rail posts  46  which are connected to handrail segment  48  and used, at least in part, to capture or otherwise secure guard panel  52 . Stated another way, each of the guard rail post mechanisms typically includes a seat mechanism (or simply “seat”) on its sides that can be used to contain or otherwise capture a sheet or piece of plywood or other material, generally by numeral  52  between (2) adjacent guard rail posts  46 . This plywood or other material can serve as the guard panel along the length of stairs  42  of the stair assembly  20 . The scaffold assembly again includes horizontal and vertical support members  30  and  32 , respectively, which are connected by bracket mechanisms  34 . 
         [0021]    Advantageously, the public access stair system  20  incorporates stringer support brackets, or stringer support bracket assemblies, which are indicated by numeral  54 . Each of the stringer support brackets  54  includes a coupler pin or coupler mechanism  55  having a pair of male projections  56   a - b  on its top and bottom sides which permit engagement (e.g., via sliding insertion) with a top end  57  of a respective vertical scaffold member  32  and a bottom end  59  of a respective guard rail post  46 . In at least some embodiments, engagement can be accomplished with the respective coupler mechanism removed from the respective stringer support bracket. The stringer support brackets  54  include plates or plate-like mechanisms, indicated by numeral  60 , and which are connected or otherwise secured to their respective coupler mechanism  55 . In accordance with at least some embodiments, the plates  60  create a saddle-like space which serves to support a respective stair stringer  40 . More specifically, the plates  60  at least temporarily hold the stringers  40  in place, thereby securing the stringers to the scaffold assembly  24 . In at least some embodiments, the saddle or saddle-like space can be a V-shaped, or substantially V-shaped space, in other embodiments the saddle-like space can be U-shaped or substantially U-shaped, and in still other embodiments, the saddle-like space can take on other geometries. The top side male projections  56   b  each include a connecting mechanism  62  which creates a connection for the respective guard rail post mechanisms  46 . In the embodiment shown, mechanisms  62  take the form of an internal snap or snap-button mechanism that serves to accomplish the respective connections via snapping engagement. Uplift bracket mechanisms  64 , connected to brackets  34 , are also incorporated and are utilized as described below. Here again, those of skill in the art will recognize that variations to the illustrated embodiment, for example, changes to the size, shape and geometry of the assembly components, are contemplated and considered to be well within the scope of the present invention. 
         [0022]    Use/Installation 
         [0023]    With reference to  FIG. 3 , in accordance with at least some embodiments of the invention, installation and/or assembly of the public access stair assembly  20  can take place as follows; a supporting scaffold  24  is typically assembled and provided (or provided and subsequently assembled) in appropriate fashion by connecting the horizontal and vertical scaffold members  30  and  32  via primary bracket members  34 ; stringer support brackets assemblies  54  are provided and connected to the supporting scaffold by engaging the male projections  56 a with the vertical scaffold members  34 ; stringers  40  (having stair units  42  or treads attached or otherwise secured thereto) are then provided and connected to the stringer support bracket assemblies via connecting elements, such as the nut  66  and bolt  67  shown; uplift brackets mechanisms  64  are then provided and connected, for example using connecting elements, such as a stringer nut  68  and bolt  69  shown, to secure the stringer support brackets and the stringers to the scaffold; guard rail posts or post mechanisms  46  are provided and connected to the stringer support bracket assemblies  54  via, for example, the snap-fit engagement described above; guard panels  52  (one of which is shown) are provided and connected to the guard rail posts  46 ; and a hand rail or hand rail segment  48  is provided and connected to the guard rail posts  46  and the guard panel  52 . It is contemplated that the above steps can be combined (so as to reduce the total number of steps), segregated (to increase the number of steps), rearranged and/or re-ordered as necessary to facilitate the installation process, and such modification(s) should be and are considered within the scope of the present invention. Dashed lines in the Figure illustrate respective engagement of the above-referenced elements. Thus, in order to disconnect or otherwise disassemble the system  20 , the above referenced process would be reversed. Those of skill in the art will recognize that variations to this method, consistent and in accordance with the various embodiments of the present invention, are contemplated and considered to be well within the scope of the present invention. Advantageously, the stringer support bracket assemblies  54  permit the stair assembly  22 , including the guard rail post mechanisms  46  and the stringer support mechanisms  40  of the stair assembly, to be connected in-line with the support scaffold assembly  24 , including the scaffold assembly vertical support members  32 . 
         [0024]    As already noted, the drawings illustrate segments or portions of an exemplary system in accordance with at least some embodiments of the invention. In practice, and although not shown, additional segments or portions, similar or identical to those shown and described herein (or similar or identical to segments or portions that are provided in accordance with other embodiments of the present invention), can be assembled, connected or otherwise provided in mechanical association with other similar or identical segments or portions to assemble a final public access stair assembly system suitable for use. Further, it is noted that installation, as described herein, is typically a manual process, however, automation of various aspects of the installation procedure are contemplated and considered within the scope of the present invention. In addition, one of skill in the art will recognize that the term “connecting” (and similar terms) used herein shall include, where appropriate, both direct and indirect connection. 
         [0025]      FIG. 4  is an enlarged side view of a portion of the public access stair system taken along line  4 - 4  of  FIG. 2 . As shown, scaffold vertical member  32  is engaged (as shown, slidably engaged) with male projection  56   a  of coupler pin mechanism  55  of the stringer support bracket assembly  54 . And guard rail post bottom end  59  of guard rail post member  46  is engaged (again as shown, slidably engaged) with male projection  56   b  of the coupler pin mechanism  55  of the bracket assembly  54 . As noted previously, engagement of the bottom end  59  with respect to the coupler mechanism  55  is accomplished, in at least the present embodiment, via snap-fit connecting mechanism  62 . Guard rail post member  46  supports and anchors guard panels  52 . Uplift bracket  62 , which is positioned adjacent a primary scaffold connector mechanism  34  and is connected to plate mechanisms  60  (one of which is shown). The plate mechanisms  60 , as noted above, serve to support stringer mechanisms  40 . The plate mechanisms are secured to the stringer mechanisms via connectors  70  and  71 , which typically comprise a nut and bolt combination. For example, and with reference as well to  FIG. 3 , connector  71  includes nut  68  and bolt  69 . Connector  71  also serves to secure the plates  60  and the stringer mechanism  40  to the uplift bracket (or “hold down”) mechanism  62 . Temporary supports  74  and  76  are shown and are included to provide support for the stringer mechanisms during assembly prior to final securing of the stringer mechanisms into position. Connectors  78   a - b  are included to secure the plates  60  to the coupler mechanism  55 , and more generally, to the stringer support bracket assembly  54 . An exemplary or representative stair unit  42  is illustrated as well. In accordance with at least some embodiments, and as shown, the stair unit  42  includes a plurality of planks  43 , or plank mechanisms, typically having treads (not shown), which are secured to representative stair unit support mechanism  44 , via connection mechanisms  47 . As shown, by way of example, the connection mechanisms include nut and bolt combinations. The stair unit support mechanism  44  is connected to the stringer mechanism  40 . In at least some embodiments, one or more stair unit support mechanisms can be integrated with one or more stringer mechanisms. 
         [0026]      FIG. 5  is a reverse bottom perspective view showing one embodiment of a public access stair system  80 . The system  80  again includes a public access stair assembly, generally referenced by numeral  82  that is connected to and supported by a scaffold assembly, which is generally referenced by numeral  84 . The scaffold assembly  84  includes horizontal scaffold members  86  and vertical scaffold or post members  88 , both of which can, but do not necessarily, take the form of tubes or tube-like structures. The scaffold assembly  84  again includes primary bracket or connector mechanisms  90  to connect the horizontal and vertical scaffold members, respectively. In accordance with at least some embodiments, the public access stair assembly  82  includes a stringer mechanisms  92 , or stringers, and the stringer mechanisms are connected to and serve to support, at least in part, stair units  94 . As noted above, each stringer  92  is a modular unit that is lightweight, and inexpensive to fabricate, transport, and handle. The stair assembly  82  further includes guard rail posts or post mechanisms  96  which are connected to and supported by the stringer mechanisms  92  and the scaffold assembly  84 . The guard rail posts  96  permit secure attachment of each hand rail segment  98  (which again are used to make up a continuous handrail or handrail assembly as noted herein). Panels  102  (two of which are shown) are included and secured to the guard rail posts and the hand rail segments  98 . Again, these panels are typically made of wood (e.g., plywood) and can be termed “guard panels” since they can generally serve to provide additional safety for users walking on the stair assembly  82 . The guardrail posts  96  also include one or more plates  97  which allow the attachment of a handrail segment  98 . In the present embodiment, each handrail segment  98  comprises an integral channel  99  that covers, or substantially covers, the top (typically exposed) edge of the plywood panels  102 . The channel can also serve to couple the handrail segment such that the assembled handrail or handrail assembly is an extended, smooth, and continuous handrail for the system  80  via plates  97  on either end of the channel. Stringer support bracket assemblies  104  are included and are used to secure the guard rail posts  96  of the public stair assembly to the vertical post mechanisms  88  of the scaffold assembly  84 . 
         [0027]    The stair assembly, including the guard rail post mechanisms and the stinger support mechanisms, are connected in-line with the support scaffold assembly, including the scaffold assembly vertical support members, such that the scaffold and stair assemblies can be integrated with one another and continuously, or substantially continuously, connected. Accordingly, a public access stair system is provided that allows for public access to and within various seating and other destinations, such as grandstands and private boxes. The access stair system is, advantageously, compatible with scaffolding systems. The system includes a stair assembly that can be installed, so as to be in mechanical association with, an applicable or desired scaffold system, and various benefits of efficiency (e.g., a minimum number of parts). 
         [0028]    Although the present invention is intended to be highly reliable, all physical systems are susceptible to failure and provision must be made for such failure. Accordingly, it is understood that safety, in an industrial process, depends on a wide variety of factors outside of the scope of the present invention including, for example, design of the system; installation and maintenance of the components of the system; the cooperation and training of individuals using the system; and consideration of the failure modes of the other components being utilized. No representation is made herein that the present invention in its various embodiments will make an industrial process safe, and no recommendation is made herein to utilize one preferred embodiment over, or to the exclusion of, another. Rather, the invention results in various advantages not achieved by prior solutions. 
         [0029]    It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein, but include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. More generally, while the present invention has been shown and described in terms of various embodiments, including at least one preferred embodiment, it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and considered to be within the scope of the appending claims.