Abstract:
An adjustable stair stringer and railing construction assembly is disclosed. The assembly is adapted to use a pair of parallel stringer arms for each side of the stair, a riser/tred support bracket for each stair, and alignment and spacing elements for spacing the support brackets along the stringers. The brackets include formations for spacing the stringers with respect to each other and for spacing adjacent brackets along the stringers. The brackets are initially pivotally attached to each of the stringers so as to be rotatably movable about their pivotal attachment as the stringers are moved axially. Axial movement of the stringers with respect to each other establishes the angle of rise of the stair. Treds and risers are attached to the brackets to form the stairs and railings are attachable to the stringer and bracket assembly to complete the construction.

Description:
This application claims priority from Provisional Application No. 60/085,151 for ADJUSTABLE STAIR STRINGER AND RAILING filed May 21, 1998 by Richard Truckner and Paul Truckner. 
    
    
     Numerous innovations for adjustable stairways have been provided in the prior art that are described as follows. Even though these innovations may be suitable for specific individual purposes to which they address, they differ from the present invention as hereinafter contrasted. 
     The prior art does not utilize a pivoted motion and does not allow an infinite amount of variable spacings when framing stairs and/or a railing. The present invention allows an infinite amount of variable spacings and use of a pivoting motion. 
     U.S. Pat. No. 2,245,825 to W. E. Ross teaches a folding stand that has pivoting support but is not based on vertical holes which keep treds in a horizontal position with an infinite amount of variable spacings. Furthermore, the patented invention utilizes different elements from the present invention. Some of the differences are: 
     1) Vertical holes are not important, 
     2) Stair is adjustable into one position only, 
     3) Not meant to be permanently fixed after moved into position on risers, 
     4) Risers and treds to not slide past each other, 
     5) Pivoting tred support is not fixed in position after adjustment and therefore not used to lock stringers. 
     U.S. Pat. No. 4,370,664 to J. J. Whitehead teaches an adjustable staircase. The patented invention does not have any pivoting motion and utilizes different elements from the present invention. 
     U.S. Pat. No. 3,885,365 to J. W. Cox teaches a self adjusting stair which utilizes a truss assemblage. In the patented invention adjustments are made using a pin and slot. The patented invention does not utilize any pivoting motion and the rails are not adjusted by stringers as with the present invention. 
     U.S. Pat. No. 3,962,838 to J. W. Cox teaches a self adjusting stair which utilizes spacers in a truss assemblage. The patented invention does not utilize a pivoting motion and the rails are not adjusted by stringers. 
     U.S. Pat. No. 4,406,347 to N. M. Strathopoulos teaches a modular staircase assembly. The patented invention does not utilize a pivoting motion. The rails are not adjusted by stringers and are not adjusted on vertical holes. 
     U.S. Pat. No. 4,959,935 to H. R. Stob teaches a prefabricated adjustable stairway. The patented invention does not utilize a pivoting motion and the rails are not adjusted by stringers. This apparatus uses a three point pivoting action so that stringers do not separate during adjustment and slide one on top of the other. 
     U.S. Pat. No. 5,189,854 to K. J. Nebel teaches an adjustable height staircase. The patented invention does not utilize a pivoting apparatus as described herein. The present invention utilizes a pivoting apparatus and contains different elements from the patented invention for at least the following reasons: 
     1) Treds are directly connected to stringers, 
     2) No risers, 
     3) No sliding motion of riser past the tred. 
     U.S. Pat. No. 4,124,957 to Pouplaw shows treds that are directly connected to stringers, stringers that have special tongue and groove spacers which must be an exact size each time in order to lock stringers otherwise the stringers must be secured top and botton of the stair only, and risers and treds do not slide past each other. 
     Numerous innovations for adjustable staircases have been provided in the prior art that are adapted to be used. Even though these innovations may be suitable for specific individual purposes to which they address, they would not be suitable for the purposes of the present invention as heretofore described. 
     SUMMARY OF THE INVENTION 
     The structure of the present invention can be used for forming a stair and may also be used as a support for concrete form work, as a form for a ramp, as a form for adjustable shelves, as an adjustable bleacher, and for adjustable displays. 
     It is an object of the present invention to provide an adjustable stringer and railing that allows users to have a quickly formed stair structure. 
     It is another object of the present invention to provide an adjustable stringer and railing that provides partially assembled elements that can be adjusted to a variety of applications and then securely fixed to form a stair framing and/or railing framing. 
     It is another object of the present invention to provide an adjustable stringer and railing that utilizes a pivoting motion. 
     It is another object of the present invention to provide an adjustable stringer and railing that allows an infinite amount of variable spacings when creating stairs and/or railing. 
     It is another object of the present invention to provide an adjustable stringer and railing that eliminates the need to calculate spacing between step treds and angle of the stairs. 
     It is another object of the present invention to provide an adjustable stringer and railing that provides an embodiment that includes an upper stringer arm, a lower stringer arm and at least one riser support. 
     It is another object of the present invention to provide an adjustable stringer and railing that provides an embodiment that includes an upper rail support and at least two railing posts pivotally attached to the upper rail support. 
     It is another object of the present invention to provide an adjustable stringer and railing that is easy and inexpensive to manufacture. 
     Another object of the present invention is the use of a bracket and setting and spacer bar that can be used with stringer elements for simplifying the formation of a stair assembly with treds, risers and rail supports. 
     Further objects of the present invention include a stair forming apparatus that includes a pivoting block to which treds and risers can be attached, a pivoting block to which treds only can be attached, a pivoting block which allows risers and treds to slide past each other, a pivoting block which allows risers and treds to be attached such that the risers and treds can be attached to each other after assembly to form a solid construction in which the risers become beams and the treds become lateral bracing to produce great structural stength and much wider stair widths than normal with on center supports (additional stringers) as with normal stairs, and greater stringer strength than with normal saw tooth stringers because of greater stringer depth and, when the riser/tred supports are secured to the upper and lower stringers after adjustment, the stringers are bonded together to form one solid stringer which also is capable of much greater spans without additional supports. 
     The structure of the present invention includes riser and tred support which allows risers and tred to slide past each other (as the stinger is adjusted) in order to utilize standard lumber and eliminate the need to cut lumber to exact widths, to use standard lumber of varing lengths according to width of the stair (i.e. 4′ to 10′ wide stairs), to use riser and tred support systems which, after pivoting and adjusting in position, allows risers to be used as beams which greatly increases the structural strength of the stair allowing much greater stair widths than normal without the need for additional center support stringers, and provides a stringer system which, when the riser/tred supports are secured, the stringer members are bonded together to form a much stronger stringer member than in normal “saw tooth” type construction giving much greater stair lengths without additional supports. 
     The foregoing benefits are accomplished with the use of a simplified bracket, spacer and setting combination that permits the assembly of a stair stringer assembly without difficulty permitting the “do it your-selfer” to install a stair assembly with simple instructions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of the stair embodiment of the adjustable stair stringer and railing illustrating two possible inclinations. 
     FIG. 2 is a side view of the railing embodiment of the adjustable stair stringer and railing. 
     FIG. 3 is a top view of the adjustable stair stringer and railing. 
     FIG. 4 is a front view showing the assembled stair and railing set in position. 
     FIG. 5 is a side view showing the assembled stairs. 
     FIG. 6 is a side view of an alternative form of the adjustable stair as assembled. 
     FIG. 7 is a side view showing the adjustable stair in two alternative rise angles using the same elements. 
     FIG. 8 is a perspective view showing the nailing block and pivot attachment plate for the stair assembly of FIG.  7 . 
     FIG. 9 is a perspective view of an alternative riser tred support. 
     FIG. 10 is a perspective view of the attachment bracket as used in the present invention. 
     FIG. 11 is a top plan view of a stair assembly of the form of FIG. 7 with risers and without the treds. 
     FIG. 12 is a sectional view of a stair assembly of the form of FIG. 7 with the use of horizontal pivots. 
     FIG. 13 is a perspective view of the tred support bracket as used in FIG.  12 . 
     FIG. 14 is an alternative form of a tred support and riser support using horizontal pivots as used in FIG.  12 . 
     FIG. 15 is an elevation view showing alternative riser/tred supports which are individually set on a two piece stringer. 
     FIG. 16 is an elevation view showing the riser/tred supports adjusted in position. 
     FIG. 17 is a perspective view of the riser/tred support of FIGS. 15 &amp; 16. 
     FIG. 18 is an alternative form of the present invention using a single pivot point for a riser/tred support. 
     FIGS. 19 &amp; 20 are alternative forms of tred support and riser support for the assembly of FIG.  18 . 
     FIG. 21 is a side elevation view with an alternative stair assembly showing riser/tred supports and setting spacing blocks. 
     FIG. 22 is a partial top plan view of a portion of FIG.  21 . 
     FIG. 23 is a side elevation view of the alternative riser/tred supports of FIG. 21 after removal of the setting/spacing blocks and as set for assembly as a stair riser and tred support. 
     FIGS. 24 and 25 are perspective views of the riser/tred support and setting/spacing block after separation. 
     FIG. 26 is a top plan view of a structure from which a bracket may be formed. 
     FIG. 27 is a top plan view of a setting and spacer bar for use with the bracket of FIG.  26 . 
     FIG. 28 is a side elevation view of FIG.  27 . 
     FIG. 29 is a sectional view taken along the lines  29 — 29  of FIG.  27 . 
     FIGS. 30,  31  and  32  are alternative forms of bracket elements with setting/spacing bars. 
     FIG. 33 is a view showing alternative adjustable spacing constructins. 
     FIGS. 34A,  34 B,  35 A,  35 B,  36 A and  36 B illustrate the use of the brackets, setting/spacer bars and stringer elements of the present invention. 
     FIGS. 37,  38 A and  38 B are side elevation views of riser formwork and locking clamp using a two piece stinger and riser/formwork supports. 
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Referring to FIG. 1 which is a side view of the stair embodiment of an adjustable stair stringer and railing  110  which includes an upper stringer arm  112 , a lower stringer arm  114  and at least one riser/tred support  116 . The upper stringer arm  112  is parallel to the lower stringer arm  114 . The riser/tred support  116  is pivotally attached to the upper stringer arm  112  and pivotally attached to the lower stringer arm  114 . The riser/tred support  116  may be attached to the upper stringer arm  112  and lower stringer arm  114  by riser/tred stringer arm fasteners  118 . The riser/tred stringer arm fastener  118  can be a pin, screw, bolt, clamp, dowel or hook. 
     The riser/tred support  116  can be in the shape of a rectangle, square, triangle, pentangle or circle. The riser/tred support  116  may be rectangular in shape and contain a riser/tred support beveled corner  116 A. Furthermore, if there are more than one riser/tred supports  116  the riser/tred supports  116  can be positioned equally along the upper stringer arm  112  and lower stringer arm  114 . The riser/tred support  116  can be attached at horizontally positioned fixed points  116 B fastened to the upper stringer arm  112  and lower stringer arm  114 . 
     The stair embodiment of the adjustable stair stringer and railing  110  can include a lower stringer support  120  which can be attachable to the upper stringer arm  112  and the lower stringer arm  114 , and an upper stringer support  122  which can be attachable to the upper stringer arm  112  and the lower stringer arm  114 . 
     The stair embodiment of the adjustable stair stringer and railing  110  can be manufactured from wood, fiberglass, metal, metal alloys, epoxy, carbon graphite, concrete or plastic. It further can be adapted for use to pour concrete and create concrete stairs. 
     The railing embodiment of the adjustable stair stringer and railing  210  as shown in FIG. 2 showing risers  80  and treds  90  contains an upper rail support  212  and at least two railing posts  214 . The two railing posts  214  are pivotally attached to the upper rail support  212 . The at least two railing posts  214  are pivotally attached to the upper rail support  212  by upper rail support railing posts fasteners  218 . The upper rail support railing post fastener  218  can be a pin, screw, bolt, clamp, dowel or a hook. 
     The railing embodiment of the adjustable stair stringer and railing  210  can contain at least one banister  216  pivotally attachable and/or attached to the upper rail support  212 . The at least one ballister  216  is parallel to the railing posts  214 . The banister  216  can be attached to the upper rail support  212  by an upper rail support banister fastener  222 . The at least one banister  216  can be positioned equally along the upper rail support  212 . The upper rail support banister fastener  222  can be a pin, screw, bolt, clamp, dowel or hook. 
     The rail embodiment of the adjustable stair stringer and railing  210  can contain an upper rail support railing cap  212 A which is attached to the upper rail support  212 . It can further contain a railing post attachment  220  attachable to each of the railing posts  214 . 
     It will be understood that each of the elements describe above, or two or more together, may also find useful application in other types of constructions differing from the type described above. 
     FIGS. 6-10 illustrate an alternative form of the stringer, riser and tred assembly in accord with the present invention. In this form a two piece stringer  310 A (lower) and  310 B (upper), as shown in FIGS. 6 &amp; 7, is first attached to a deck or wall vertical surface by an attachment bracket  312 , as shown in FIG. 10, with the two pieces of the stringer attached to pivot holes  312 A in the bracket. Riser/tred supports  314  having pivot holes  316  spaced the same distances as the pivot holes in the attachment bracket are spaced along the risers and are fixed to the risers by suitable means at screw holes  318  to cause the riser/tred supports to be parallel to the attachment bracket and equally spaced along the risers. These vertical pivot riser/tred support  314  are unique because the supports pivot for adjustment only and are fixed in position after adjustment; the fixing of the riser/tred supports joins the two pieces of the stringer to form a one piece, permanently adjusted stringer which is structurally superior to normal stair construction; the positioning of the pivot points (opposite risers) allows the top of the stair to be attached the same distance down from the deck/floor level each time regardless of the riser height because all risers adjust equally including the first riser; the configuration of the riser/tred support allows risers  80  and treds  90  to slide against each other for adjustment; and when the risers are attached to the riser/tred supports and the treds, each riser then acts as a beam giving the stair much greater structural stability and allowing greater widths for a stair without additional supports. The riser/tred supports  314  can be constructed from metal, composites and other materials. It should be evident that the riser/tred supports  314  are now vertical if the surface of the deck where attachment was made was vertical when the attachment bracket was attached, and as illustrated in the two positions shown in FIG. 7, the riser/tred supports are now in position to be permanently attached to the stringers at securing holes  318  and to have risers  80  and treds  90  attached to the supports. 
     FIGS. 12-14 illustrate an alternative form of the stringer, riser and tred assembly formed using horizontal pivoted tred support brackets and including an alternative tred support with riser support elements. FIG. 13 shows alternative pivoting tred supports using a straight bracket  412  and FIG. 14 another support  414 , which is truncated in shape which can be used with or without a riser, but allowing greater fixing to the stringer. Riser  80  and treds  90  can still slide past each other to form beams. There are three steps shown on the drawing which illustrates how this system would be installed with pivot points that are horizontal. 
     The feature of the riser/tred support in either the vertical or horizontal pivoted form is that it is a one piece apparatus which attaches to the two piece stringer using two pivot points which normally are vertical or horizontal but can be at any common angle. The riser/tred supports pivots to adjust for a required height to form the correct stair profile. The riser/tred support is then fixed in position (using nails, screws, bolts, glue, etc.) against the two piece stringer to form one solid, non-moving stringer which is capable of supporting both risers and treds or treds alone or risers alone (when being used for concrete formwork). The two piece stringer is then cut (at the dotted lines shown) to conform to the deck or wall at the top and the base at ground level at the bottom. The riser/tred support allows risers and treds to slide past each other so that the risers can be adjusted for height sliding up or down past the back of the tred. The back of the tred is pushed against the face of the riser to form an enclosed stair. The position of the risers and treds can vary infinitely in respect to each other depending on the stair adjustment. 
     FIGS. 15-17 illustrate a further alternative form for riser/tred supports  512  which are individually set on a two piece stringer  310 A and  310 B using removable setting blocks  514  and setting pins  516 . In this form the removable setting blocks  514  are used to space the riser/tred supports equally along the two piece stringer by being placed on a reference surface of a support and as their ends abut along the stringer. The stringer pieces are separated from each other by the removable setting pin  516  and the riser/tred supports  512  are attached at their pivot points  518 A and  518 B to the stringer  112  and to the stringer  114 . When the setting blocks  514  and the setting pins  516  are removed, the two parts of the stringer can be slid with respect to each other to adjust the riser/tred supports  512  in the desired vertical position and the riser/tred supports can then be secured to the stringers by screws, nails, or other fasteners at securing holes  520 . The riser/tred supports are then in position for the attachment of equally spaced treds and risers. 
     FIGS. 18-20 illustrate a stair section showing pivoting riser/tred supports using a single pivot point allowing the tred to be set level after stringer installation. Equally spaced support brackets  612  are pivoted at a single pivot  614  position of the stringer with those pivot positions being located the same distance below the deck/floor when the stringer is attached with the pivot position a desired distance below the level of the deck or floor to which the stair is to be attached. With a single pivot point for each of the equally spaced riser/tred supports, the supports can be attached to the second stringer by suitable means and the treds will always be equally spaced and will have equal rising distances. The single pivot point can be at any common point (shown as alternatives  614 B) along the riser/tred support brackets  612  and the brackets can be just a tred support or a tred and riser support. FIG. 20 illustrates an alternative form  612 B for the bracket in a truncated form. 
     FIGS. 21-25 illustrate another alternative form for riser/tred supports for use in the present invention. In this form the riser/tred supports  712  are individually set on a two piece stringer  112 - 114  using removable setting/spacing blocks  714 . This form of two piece stringer/riser/tred support assembly can be assembled with the stringers  112 - 114  and the riser/tred supports  712  in place by attachment means at the pivots  712 A and with the riser/tred supports spaced by the body  716  of setting/spacing blocks  714  mating and cooperating extensions  718 A and  718 B with centering slots  720 A and  720 B in the riser/tred supports. When the assembly is to be used,  720 A and  720 B in the riser/tred supports. When the assembly is to be used, the setting/spacing blocks can then be removed from the riser/tred supports and the stringers can then slid with respect to each other to rotate the riser/tred supports about their pivot points. The stringer can then be attached to the face of the deck or wall where the stair is to be attached and the stringers can be cut (at possible cut lines shown) to face against the deck or wall. The riser/tred supports will then be equally spaced both vertically and horizontally, can be attached by suitable fastening means to the stringers, and are in position for installation of risers and treds. 
     FIGS. 26-33 illustrate another alternative form for a riser/tred support bracket  812 . This form may be formed from a metal or other suitable material blank  812 A with stamped holes, slots and side portions to from the bracket. The side protions  813  and  814  from the tred and riser support surfaces (respectively) with stamped holes  815  for attaching means for the treds and risers. Pivot holes  816  are used for connecting the bracket to the stringers and holes  817  are for fixing the bracket in place when a stringer assembly is completed. The bracket  812  is provided with stamped alignment guide holes at  819  and a guide slot at  820 . 
     FIGS. 29-31 illustrate a setting and spacing bar  822 . The setting and spacing bar may be formed of metal or other suitable material and includes a central body portion  823  with folded ears  824  at each side and with a guide tab  825  formed at each end of the body portion. 
     The setting and spacing bar  822  is adapted to cooperate with and space two brackets  812  by aligning the guide tab  825  with the guide hole  819  at one bracket and with guide slot  820  in the next bracket and serves to establish the spacing between brackets. The folded ears  824  separate two stringers and thus to allow for the space for relative movement between stringers. 
     With at least a pair of brackets  812  spaced by setting and spacing bars  822  and an upper and lower stringer the brackets may be attached by suitable means to the stringers at the pivot holes  816  to provide aligned and spaced riser/tred brackets for a stair assembly as will be described with reference to FIGS. 34-38. 
     FIGS. 30-33 illustrate alternative forms for riser/tred brackets similar to that shown in FIGS. 26-29. FIG. 30 illustrates a bracket  812  with a setting and spacing bar  822  integrally formed with the bracket. The bar  822  has a length designed to space adjacent brackets and a near central folded ear portion  824  for spacing stringers. The bar  822  would be detachable after it has functioned in setting and spacing. FIG. 31 illustrates another alternative of an integrally formed bracket  812  with a removable spacing bar  822  and a central setting body  824 . FIG. 32 is another alternative bracket similar to FIG. 31 with a removable spacing bar  822  and a central plug  826  for spacing the stringers. FIG. 33 illustrates alternative forms for the end of a spacing bar  822  to adapt the bracket to different spacings of brackets along a stringer assembly. The spacing bar may include holes or pins at  822 A or notches at  822 B. Spacing bars of the type shown here can be used with the brackets  116  shown in FIG. 5 by cooperating with the spacer slots  115  in positioning brackets  116  before stringers  112  and  114  are moved relative to each other in setting the brackets  116  for receiving treds and/or risers. 
     FIGS. 34-36 illustrate the use of the brackets with stringers in the formation of a stair assembly. FIGS. 34A and 34B illustrate the opposite sides of a stair stringer assembly, each side having an upper  112  and lower  114  stringer with a plurality of brackets  812  of the type illustrated in FIGS. 26-29 (or of the types shown in FIGS. 1-25) and employing setting and spacing bars  822  to position the brackets along the stringers. The two stringer assemblies mirror each other to be left and right sides of a stairway. When assembled, spaced and guided, the brackets are attached to the stringers by suitable means through pivot holes  316 . FIGS. 35A and 35B illustrate the moved portion of the stringers  812 - 814  and the rotation of the brackets  812  to the deaired position for attachment to a deck or wall and for tred and riser attachment after cutting the stingers for attachment to the deck or wall. At this stage in the formation of the stringer assembly the brackets  812  can be permanently attached to the stringers at the provided attachment holes. 
     FIGS. 36A and 36B illustrate the completed stair using the brackets and movable stringers of the present invention. It should be noted that the forward holes  815  along the tred side portions  813  of the bracket of FIG. 26 premit the location for predrilling guide holes into a tred from below. By knocking the tred against the bracket, the raised holes will mark the underside of the tred. Predrilling guide holes will permit ease of assembly of the tred from below before a riser is added to the face of the stair. 
     FIGS. 37 and 38A illustrate the use of the principle of the present invention for the positioning of formwork for poured concrete stairs. The use of two part parallel stingers with pivoted riser/formwork supports permits the setting of equally spaced horizontal riser forms and equally spaced vertical spaces between poured stairs. The two piece stringer is first set at the desired angle and the separated stinger parts are fixed with respect to the top and bottom of the desired stair. Equally spaced riser/formwork supports are positioned along the risers by attachment at pivot points with the support elements having adjustment slots (FIG. 37) or by the use of locking holders (FIG.  38 B). Riser formwork elements are attached to the free end of each of the supports. Concrete aggregate can then be poured behind each of the riser formworks to the desired level for the stairs and allowed to set. It should be evident that the face of the riser formwork elements can be adjusted to a desired angle other than vertical by adjusting the relative positions of the two stringer elements. The riser height adjustment can be achieved by setting the first and last support and their riser formworks in position and then raising or lowering intermediate supported riser formworks to a string line drawn from the first to the last support. Equally spaced horizontal supports will then result in equally spaced vertical riser formworks. 
     While certain preferred embodiments of the invention have been specifically disclosed, it should be understood that the invention is not limited thereto as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpertation within the terms of the following claims.