Patent Publication Number: US-2007102690-A1

Title: Apparatus and method for assembling a balustrade system

Description:
FIELD OF THE INVENTION  
      This invention relates to construction systems for the provision of railings, fencing, balustrading or the like. In particular the invention relates to construction systems which are pre-fabricated and installed on-site.  
     BACKGROUND  
      In the provision of railings, fencing, balustrading or the like, it is common for more or less horizontal railing members to be welded to stanchion members on-site, with the welded parts subsequently being ground smooth and polished. Welded assembly is the most common construction method where components are made from stainless steel, as is the case in many architectural applications. Hand welding of stainless steel is a skilled process which adds to the installed cost of railings or balustradings and frequently results in unsightly local heat distortion of welded components. Lower cost construction systems in which structural components are simply bolted or clamped together are well known in the art, but these are frequently aesthetically unattractive. As a result, they are unsuited for many architectural applications.  
      Where railing and balustrading construction systems incorporate aesthetically attractive joining means, these usually involve the employment of specially manufactured, expensive components. In some examples, generally cylindrical joint members are employed to join stanchion and rail members. The joint members are complex in shape, clearly expensive to manufacture, are somewhat limited in the structural arrangements which they permit and, from an aesthetic standpoint, appear somewhat mechanical.  
      In other examples, specially manufactured, shanked fittings are permanently fixed to stanchions with suitable fastenings and the ends of rail members are slipped over the shanks of the fittings. The internal and external diameters, respectively, of the rail members and shanks are such as to provide a neat sliding fit and the ends of the rail members are retained in place on the shanks by the wedging action of O-rings accommodated in suitably shaped, tapered grooves in the shanks. While this arrangement provides some ease of assembly, in some applications, long-term hardening and deterioration of the O-rings as a result of temperature extremes may be expected with a possible loss of structural integrity. Additionally, where they are required, intermediate vertical rails between upper and lower horizontal rails are still required to be welded into place. The arrangement thus does not properly fill the need for a relatively low cost, easily assembled, permanent structure.  
      Consequently, there is a need for a cost-effective balustrade system which allows on-site assembly without the need for welding.  
     SUMMARY  
      The present invention is a balustrade system which allows on-site assembly without welding and a method for assembling the balustrade system.  
      In one embodiment, the balustrade system comprises one or more primary members. One or more toroido-cylindrical shaped nodal rings are secured to the primary member. One or more socket fittings are secured to one toroido-cylindrical shaped nodal ring. Each socket fitting defines a socket bore. A secondary member is secured within the socket bore.  
      In one embodiment of an apparatus for connecting the primary and secondary members of the balustrade system, the apparatus comprising a toroido-cylindrical shaped nodal ring. The toroido-cylindrical shaped nodal ring is adapted to be positioned on the primary member. The apparatus also comprises one or more socket fittings adapted to receive a secondary member and a means for engaging the toroido-cylindrical shaped nodal ring with the socket fitting.  
      In one embodiment of a method for assembling the balustrade, the method comprises positioning a toroido-cylindrical shaped nodal ring onto a primary member and securing the toroido-cylindrical shaped nodal ring to the primary member. The method also comprises securing a socket fitting to the toroido-cylindrical shaped nodal ring and securing a secondary member within a socket bore defined by the socket member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a view of a nodal assembly fixed at an intermediate position on a stanchion member;  
       FIG. 2  is a longitudinal cross-sectional view of a nodal assembly and cap fitting fixed at the top of a stanchion member;  
       FIG. 3  is a longitudinal cross-sectional view of alternative means of fixing a toroido-cylindrical shaped nodal ring to a stanchion member;  
       FIG. 4  is a longitudinal cross-sectional view of the toroido-cylindrical shaped nodal ring depicted at  FIG. 3  fixed to a stanchion member using alternative means;  
       FIG. 5  is a transverse cross-sectional view of the arrangement depicted at  FIG. 4 ;  
       FIG. 6  is a longitudinal cross-sectional view of further alternative means of fixing a toroido-cylindrical shaped nodal ring to a stanchion member;  
       FIG. 7  is a side view of panel members supported between adjacent stanchion members;  
       FIG. 8  is a longitudinal cross-sectional view of further alternative means of fixing stanchion members to a supporting surface;  
       FIG. 9  is a longitudinal cross-sectional view of means of fixing stanchion members to a supporting surface;  
       FIG. 10  is a longitudinal cross-sectional view of alternative means of fixing stanchion members to a supporting surface;  
       FIG. 11  is a longitudinal cross-sectional view of alternative means of fixing socket fittings to toroido-cylindrical shaped nodal rings;  
       FIG. 12  is a side view of the fastener forming part of the means depicted at  FIG. 11 ;  
       FIG. 13  is a partial side view of an alternative arrangement of rail and stanchion members.  
    
    
     DETAILED DESCRIPTION  
      Referring now to  FIG. 1 , one embodiment of the balustrade system is depicted. The balustrade system includes one or more primary members. As shown, the primary member of the balustrade system is a more or less vertically arranged stanchion member  1 . One or more toroido-cylindrical shaped nodal rings  2  are positioned on the primary member. The shape of the nodal ring is more or less that of a toroid from which material has been removed internally to create a cylindrical bore  3  passing through the full thickness of the toroid and collinear with its axis, the diameter of the bore being such as to provide an easy sliding fit on the stanchion member.  
      One or more suitably positioned, radially-arranged, extended grub screws  4  are screwed into threaded bores  8  provided in the nodal rings and, when tightened with a suitable tool engaging shaped recess  9 , act to lock the nodal ring securely to the stanchion member.  
      O-rings (not shown) of a suitable material are accommodated in grooves  5  provided in bore  3  and act to provide a resilient bearing surface between the surface of cylindrical bore  3  and the external surface of stanchion member  1 , thereby preventing the nodal ring from marring the polished external surface of the stanchion member.  
      One or more socket fittings  6  are secured to one toroido-cylindrical shaped nodal ring  2  by a means for engaging the toroido-cylindrical shaped nodal ring to the socket fitting  6 . Each socket fitting defines a socket bore  11  adapted to receive a secondary member.  
      In one embodiment, the means for engaging the toroido-cylindrical shaped nodal ring to the socket fitting is a threaded extension of the grub screws  4 , which extends beyond the external surface of the nodal ring. The threaded socket bores  10  of socket fittings  6  are screwed onto the threaded extensions and tightened using a non-marring, strap-type wrench of leather or textile material. The threaded socket bores are made collinear with the longitudinal axes of the socket fittings.  
      The ends of a secondary member  7 , in this case a rail, are accommodated within the socket bores  11  of the socket fittings and O-rings (not shown) of a suitable material are accommodated in grooves  12  provided in the socket bores  11 . The O-rings act to provide a resilient bearing surface between the surface of the socket bore  11  and the external surfaces of the secondary members  7 , thereby preventing the nodal ring from marring the polished external surface of the rail members.  
      In alternative embodiment, a suitable adhesive compound, such as two-part epoxy adhesive, is employed to bond the nodal rings and the socket fittings, respectively to the primary members and the secondary members.  
      In one embodiment, the end surface of the socket fitting abutting the nodal ring is made flat and a complementary flat surface is provided on the external surface of the nodal ring. In an alternative embodiment (depicted as  29  in  FIG. 8 ) the end surface of the socket fitting is provided with a shape complementary to that of the external surface of the nodal ring.  
      In a further embodiment, suitable solid or substantially solid, close-fitting plugs (not shown) are provided in the the primary members to support the primary members against collapsing forces applied by the grub screws.  
      For the purpose of general description, the term, primary member, may be taken to mean a member of larger diameter to which a member of smaller diameter, a secondary member, is fixed. In the preceding explanation, the stanchion members are primary members and the rail members are secondary members. In more complex arrangements, the rail members may, in turn, become primary members and have fixed to them tertiary members, such as a cross rail.  
      Referring now to  FIG. 2 , a nodal arrangement similar to that depicted in  FIG. 1  is provided at the top of stanchion member  1 . A plug-type cap  13  is provided to close the upper end of the stanchion member, cylindrical shank  14  of the cap forming a neat sliding fit with cylindrical bore  3  of nodal ring  2  and the cap being secured in place on the nodal ring by one or more grub screws  16  being screwed into threaded bores  15  provided in the cylindrical shank and tightened to engage upper O-ring groove  5 . The cap may be fixed to the nodal ring prior to its positioning on the stanchion member.  
      While the nodal ring must retain the toroido-cylindrical shape, the socket fitting and the cap may be shaped in any desired way to meet the aesthetic requirements of a railing or balustrade installation.  
      In another embodiment the cylindrical shank of the cap fitting may be made solid or substantially solid and sufficiently long to extend into the bore of the stanchion member beneath a the nodal ring positioned at the top of the stanchion member and, by making a close fit with the inner surface of the stanchion member, to support the stanchion member against collapsing forces applied by the grub screws.  
      With reference to  FIGS. 3, 4  and  5 , alternative means are provided to lock nodal rings  2  to stanchion members  1  in situations in which the extended grub screws cannot be used. In a first means, apertures  17  are provided in the stanchion member and a circumferential groove  18  is provided in the cylindrical bore  3  of the nodal ring. A locking bar  20  is elastically distorted to allow it to enter the bore  19  of the stanchion member and is positioned using a suitable extended tool such that its ends  21  extend elastically through the apertures  17  and into the circumferential groove  18 . The locking bar can be made from an elastic metal, such as spring steel, and is provided along part of its length with convolutions which facilitate its elastic deformation. The corners of the ends of the locking bar are preferably formed into points which engage the surface of circumferential groove  18 , thereby acting to prevent rotation of the nodal ring on the stanchion member. Removal of the locking bar using a suitable extended tool permits the nodal ring to be removed from the stanchion member.  
      With reference to  FIG. 6 , further alternative means are provided to lock nodal rings  2  to stanchion members  1  in situations in which the extended grub screws cannot be used. In this arrangement, one or more small grub screws  22  are screwed into the threaded bores  23  provided in and passing more or less radially through the nodal ring. When tightened, the grub screws  22  engage the stanchion member  1  and lock the nodal ring to it. In one embodiment, the threaded bores angle upwardly from the lower surface of the nodal ring. In this position the bores are minimally conspicuous. In alternative embodiments, the threaded bores are positioned anywhere on the nodal rings.  
      With reference to  FIG. 7 , provision is made for panel members  24  to be supported between adjacent stanchion members  1 . Stanchion members  1  are fixed to supporting surface  27  with fixing means including dress piece  28  and assembled to rail members  25  in the manner previously described. Additionally, the nodal rings  2  are fixed to the stanchion members  1  in intermediate positions and panel supporting members  26  are fixed to the additional nodal rings using suitable flush fastenings. In the preferred embodiment, the panel supporting members  26  take the form of a more or less square channel made from a suitable material and are lined with a suitable resilient material to positively grip the edges of the panel members. The panel supporting members  26  are closed at their lower ends to retain the panel members  24  within them. In an alternative embodiment, the panel supporting members  26  are fixed directly to the stanchion members  1 . The panel members  24  may be made from any suitable material.  
      With reference to  FIG. 8 , means are provided to fix the stanchion member to a supporting surface. In this arrangement, stanchion member  1  is fixed to mounting flange  63  by one or more mounting bore grub screws screwed into threaded holes  66  provided in the mounting flange  63 . In one embodiment, O-rings (not shown) are accommodated in suitable grooves  65 ,  70  provided in mounting bore  64  of the mounting flange  63  to prevent the mounting flange  63  from marring the polished external surface of the stanchion member. The mounting flange  63  is, in turn, fixed to the supporting surface by suitable fastenings (not shown) passing through attachment holes  67  provided in the mounting flange. In an alternative embodiment (not shown), the mounting flange  63  is provided with a deep chamfer or other circumferential recess at point  68  and the end of the stanchion member is fixed to the mounting flange by welding into the chamfer or circumferential recess, such that the welding bead does not obtrude from and prevent the seating of the mounting flange  63  on the supporting surface.  
      With reference to  FIG. 9 , alternative means are provided to fix the stanchion members to a supporting surface. In the simplest embodiment, the stanchion members  1  are simply cast into the supporting surface, supported in correct alignment by suitable means until the concrete or other material from which the supporting surface is made has properly set.  
      In one embodiment, an anchor tube  35  is cast into the supporting surface, supported in correct alignment by suitable means until the concrete or other material from which the supporting surface is made has properly set. A flange  40  is provided on the lower end of the anchor tube  35  to better secure the anchor tube in the supporting surface. The lower end  34  of the stanchion memeber is inserted into the anchor tube  35  for a suitable distance, the diameters of their complementary surfaces being such as to make a tight sliding fit. One or more pairs of corresponding holes  48  are drilled through the anchor tube  35  and the stanchion member  1  and roll pins  36  or other suitable fastenings are driven or inserted through them to fix the stanchion member  1  to the anchor tube  35 . A dress piece  28  is placed on and positioned at the bottom of the stanchion member and secured in place by a locking bar  39  inserted as described in relation to  FIGS. 3, 4  and  5  through opposed apertures  37  in the stanchion member to engage groove  38  provided in the dress piece. In one embodiment, an O-ring (not shown) is accommodated in a suitable groove (not shown) provided in the upper part of the dress piece to prevent the dress pieces from marring the polished external surfaces of the stanchion member. In an alternative embodiment, the dress piece  28  is fixed to the base of the stanchion member using grub screws as described in relation to  FIG. 6 . In an alternative embodiment, the anchor tube  35  may be made smaller in diameter and the stanchion member  1  positioned over its exterior.  
      With reference to  FIG. 10 , further alternative means are provided to fix the stanchion members to a supporting surface. In this arrangement, anchor bolt  43  is cast into supporting surface  27  and a mounting boss  41  secured to threaded upper part  45  of the anchor bolt  43  by the tightening of suitable nut  46 . In one embodiment, a lug  44  is provided on the lower end of the anchor bolt  43  to better secure the anchor bolt in the supporting surface. The lower end  34  of the stanchion tube is positioned over the mounting boss  41  with its end surface abutting flange  42  provided at the bottom of the mounting boss  41 , the diameters of their complementary surfaces being such as to make a tight sliding fit. One or more pairs of corresponding holes  47  are drilled through the anchor tube and the mounting boss and roll pins  36  or other suitable fastenings are driven or inserted through them to fix the stanchion member to the mounting boss. Dress piece  28  is placed on and positioned at the bottom of the stanchion member and secured in place by a locking bar  39  inserted as described in relation to  FIG. 9 . In one embodiment, an O-ring (not shown) is accommodated in a suitable groove (not shown) provided in the upper part of the dress piece to prevent the dress piece from marring the polished external surface of the stanchion member. In an alternative embodiment, the dress piece is fixed to the base of the stanchion member using grub screws as described in relation to  FIG. 6 .  
      With reference again to  FIGS. 1 and 2 , where a horizontal rail member  7  is to be fixed between two stanchion members  1  in fixed positions, it is cut to a length such that, with its ends fully inserted into socket bores  11  of socket fittings  6 , the outer ends of the socket fittings can just be accommodated between the ends of grub screws  4  screwed into nodal rings  2 . The socket fittings  6  are slid outwardly on the horizontal rail member to introduce the ends of the grub screws into threaded socket bores  10  of the socket fittings  6  and the socket fittings  6  are turned to engage the threaded socket bores  10  and screw the socket fittings fully and tightly onto the socket fittings.  
      With reference to  FIGS. 11 and 12 , alternative means are provided to fix a the horizontal rail member between two the stanchion members in fixed positions. In this embodiment, nodal rings  2  are secured to stanchion members  1  by one or more grub screws  62  in the manner previously described. The grub screws  62  are of a length such that they protrude only slightly from the nodal ring when tightened. Counter bores  49  are provided in the nodal ring around the grub screws  4 .  
      In one embodiment, the counter bores  49  extend through approximately half the depth of the nodal ring. A bolt bore  51  is provided through socket fitting  6  collinear with its longitudinal axis. The bolt bore  51  can be provided with one or more splines, keys or other locating means  53 . Hollow bolt  52  passes freely through bolt bore  51  of the socket fitting  6 , but the hollow bolt  52  is constrained from independent rotational movement in relation to the socket fitting by complementary locating means  54  provided on the outer shank of the hollow bolt. The hollow bolt is provided with a threaded interior bore  55  which is adapted to be screwed over that part of the grub screw exposed within counterbore  49 , causing plain inner shank  56  of the hollow bolt to enter the counterbore.  
      A spring retaining pan  59  made from a suitable light material is pressed into horizontal rail member  7  and retained by friction. The head  57  of the hollow bolt is provided with spring locating boss  58  and bolt projection spring  61  is located between the spring locating boss and a similar boss  60  formed on the spring retaining pan. In use, the nodal ring is secured to the stanchion member by screwing one or more the grub screws  62  into threaded bores  8  and tightening them against the stanchion member. The hollow bolt  52  is pushed back into the socket fitting  6  against the urging of the bolt projection spring  61  and the end of the socket fitting  29  aligned with the grub screw, permitting the hollow bolt to index with the outer end of the grub screw. The socket fitting  6  is then turned to screw the hollow bolt  52  onto the grub screw  62 , the hollow bolt being tightened against the nodal ring using a non-marring, strap-type wrench of leather or textile material to turn the socket fitting.  
      Where the socket fitting  6  is to be fixed to a fixing surface other than a stanchion member, attachment means in the form of a double-ended bolt (not shown) are employed. One part of the double-ended bolt is provided with a coarse, tapered thread similar to that of a coach bolt. The other part of the double-ended bolt is provided with a conventional parallel thread complementary with that of the socket fitting. A flatted, medial collar is provided between the two the threaded parts. In use, the tapered threaded part of the bolt is screwed and tightened into a suitable bore in the fixing surface, being turned by means of a suitable tool applied to the flatted collar. The socket fitting is then screwed and tightened onto the parallel threaded part in the manner previously described.  
      With reference to  FIG. 13 , rail member  7  is fixed to nodal ring  2  at an angle. This is achieved simply by providing threaded bores  8  in the nodal ring at a suitable angle and then assembling the components in the manner previously described.  
      In all cases in which a the nodal ring  2  is fixed to a the stanchion member using one or more the grub screws, a support piece (not shown) made from a short length of thick-walled tubing or solid cylinder of a suitable hard material having an external diameter slightly less than that of the stanchion member is inserted into the interior of the stanchion member to support the stanchion member and prevent its collapse inwardly as a result of the high, localized force generated by the grub screws.  
      In the method of the present invention, the method of assembling a balustrade system comprises the steps of: positioning a toroido-cylindrical shaped nodal ring  2  onto a primary member  1 ; securing the toroido-cylindrical shaped nodal ring  2  to the primary member  1 ; securing a socket fitting  6  to the toroido-cylindrical shaped nodal ring  2 ; and securing a secondary member  7  within a socket bore  11  defined by the socket member  6 . The method can included forming the socket fitting in a decorative shape.  
      In the one embodiment of the method (as shown in  FIG. 4 ), the toroido-cylindrical shaped nodal ring  2  can be secured to the primary member  1  by placing a locking bar  20  within the primary member and engaging the ends of the locking bar  21  with a circumferential groove  18  defined by the toroido-cylindrical shaped nodal ring  2 . To do this, the locking bar is passed through one or more apertures defined by the primary member.  
      In another embodiment of the method (as shown in  FIG. 1  ),the toroido-cylindrical shaped nodal ring  2  can also be secured to the primary member  1  by tightening one or more grub screws  4  against the primary member  1 . The grub screws  4  are accommodated within one or more threaded bores defined in the toroido-cylindrical shaped nodal ring.  
      In one embodiment, the method further comprises the step of securing the socket fitting  6  to the toroido-cylindrical shaped nodal ring  2  by engaging a threaded socket bore  10  defined by the socket fitting  6 , with threaded extension of the grub screw  4  extending beyond the toroido-cylindrical shaped nodal ring.  
      In another embodiment, the method further comprises the step of protecting the surface of the primary member by fitting one or more O-rings within a groove  5  defined by the toroido-cylindrical shaped nodal ring  2 . This is done so that the O-ring frictionally retains the toroido-cylindrical shaped nodal ring  2  in place during assembly.  
      In yet another embodiment depicted in  FIGS. 7, 8 ,  9 , and  10 , the method further comprises the step of fixing an end of the primary member  1  to a supporting surface  27 . This method can comprise fitting a dress piece  28  around the primary member  1 . The dress piece  28  defines one or more threaded dress piece bores. The dress piece is abutted to the supporting surface  27  and secured to the primary member  1  with one or more dress piece grub screws extending through the threaded dress piece bores. The primary member  1  can be fixed to the support surface  27  by casting the end of the primary member into the support surface.  
      The primary member can also be fixed to the support surface  27  by casting an anchor tube  35  into the support surface  27 . The primary member  1  slides into the anchor tube  35  and is secured to the anchor tube  35  by engaging a fastening means through both the primary member  1  and the anchor tube  35 .  
      Alternatively, the primary member can be fixed to the support surface by casting an anchor bolt  43  into the supporting surface  27 . A mounting boss  41  is secured to the anchor bolt  43  by tightening a nut  46 . The mounting boss  41  is secured to the primary member  1  by engaging a fastening means through both the primary member and the mounting boss.  
      Finally, the primary member  1  can be fixed to the support surface  27  by fastening a mounting flange  63  to the support surface  27 . The mounting flange  63  comprises a mounting bore  64  adapted to form a sliding fit around the primary member  1 . The mounting bore  64  defines one or more threaded holes  66 . The primary member is placed in the mounting flange. One or more mounting bore grub screws are engaged with the exterior surface of the primary member  1 . The mounting bore grub screws are positioned in the threaded holes  66 .  
      In a final embodiment of the method, the method comprises securing a second socket fitting to a fixing surface with a double ended bolt. One end of the secondary member is secured within the second socket fitting. Examples of suitable fixing surfaces include a wall and a beam.