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[0001]    This application is based on the provisional patent application 61/213,858 filed on Jul. 22, 2009. The present invention relates to a handrail assembly, and more particularly to an assembly that can be easily attached to almost any place where ambulatory support is necessary, being a wall in a residence, inhabited space, or outside vertical surface. This assembly is easy to install, remove, and very inexpensive to manufacture. It provides a modular solution to the growing population of aging citizens, and can extend a user&#39;s period of independent home living by several years. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Demographic statistics show an aging population. Older people are more prone to injuries and ailments that impair their mobility, and benefit from installation of railings that minimize risk of falling. Stroke victims are often incapable of using a walker requiring strength in both arms and must have secure railings to remain ambulatory. Railings are especially important in washrooms, shower stalls, kitchens and other occupancies with floors that are not always slip-resistant. Exterior walks and ramps subject to ice formation are safer with handrails secured to adjoining walls. Building codes mandate railings along stairways. The large and growing market will benefit from the availability of quickly installed, economical handrails that this invention promises. 
         [0003]    There is known U.S. Pat. No. 3,162,425, which describes a hand rail for stairways using clamps to affix a railing to a wall. However, this uses regular screws to attach the rail to the clamps, and requires a lot more time to install or modify its location. 
         [0004]    There is also known U.S. Pat. No. 3,306,641, which uses knurls to hold a railing in place. However, this design is flawed due to the fact that it is not resistant to abrupt twisting impacts, as it is installed to be removable by a twisting motion. It is also more expensive to produce. 
         [0005]    There is also known U.S. Pat. No. 5,529,288, wherein a railing is slid into place over a support means and immobilized by screws. This design is also not as easy to use as the present invention, as it requires immobilization by screws. 
         [0006]    The present invention overcomes the drawbacks of the cited prior art: it provides a rigid handrail, very easily installable in almost any environment, and very inexpensive to manufacture. This invention can be sold in any hardware store, with self-explanatory instructions for the do-it-yourselfer or handyman. 
       OBJECT OF THE INVENTION 
       [0007]    It is the object of the present invention to provide a secure handrail assembly for users with impaired mobility, this system being easily installable to any surface encountered in a residential or commercial environment, and priced very affordably. 
         [0008]    These goals are accomplished by a standardized assembly comprising only two components: a railing and a bracket. The bracket head mates with a channel inside the railing to be immobilized at any point in the railing, resulting in an aesthetically-attractive handrail that can be installed in corridors, halls, rooms, and anywhere else a user requires a hand-hold. 
         [0009]    Due to the simplicity of the present invention and its components, its cost can be greatly reduced if compared to the current state of the art. Components can be sold directly to the consumer, and proper installation can be performed in minutes. 
       SUMMARY OF THE INVENTION 
       [0010]    The system consists of handrails supported on brackets secured to walls. The handrails: 
         [0000]    1. Are cut to any convenient length; minimizing the number of joints improves the appearance, comfort and security of the railings and provides users with uninterrupted support for hand movement.
 
2. Are designed to be fitted with brackets that are easily and securely twisted into place anywhere along their length without use of tools.
 
         [0011]    Prior to installation: 
         [0000]    1. Any studs or furrings within the walls are located,
 
2. The brackets are twisted into the handrail to suit the spacing of any studs or furrings; on solid walls (i.e. masonry, concrete) the brackets are set at intervals recommended in installation instructions.
 
3. The assembled handrail-bracket lengths are screwed through the wall finishes to the studs or furrings within the walls, or directly to solid surfaces, using conventional fasteners.
 
         [0012]    The preferred embodiment of the present invention comprises the following elements: 
         [0013]    Handrails: In the preferred embodiment, the handrails are aluminum tubular extrusions with factory applied coatings or anodized surfaces. The handrail has a channel that is designed to receive a bracket&#39;s head. These brackets can be twisted into place anywhere along the rail&#39;s length. The brackets can just as easily be unlocked by twisting them in the opposite direction. The handrails are cut to any desired length. If the handrail is made of a flexible material, the ‘twist-lock’ principle is facilitated by the vertical stress-relief channel forming part of the handrail extrusion; this allows the handrail channel to flex to receive the diagonal dimension of the bracket head during installation without distorting the exterior profile. In the preferred embodiment of the present invention, in cross-section, the channel is of a T-shape configuration. If the rail is made of a rigid material such as heavy-gauge aluminum, the channel can be of an uppercase “T” configuration, since the material will not flex. If the rail is made of a more flexible material, the channel can be of a lowercase “t” configuration, wherein the uppermost part of the channel comprises the stress-relief channel. 
         [0014]    Brackets: Brackets of aluminum, steel, zinc, brass or any other material strong enough to support the weight of the user are designed to twist into the handrail; no fasteners are required. The bracket&#39;s wall support portion is flat, permitting it to be securely fastened directly and tightly to masonry or concrete, or through drywall finishes secured over metal or wood studs or furrings. Holes are provided to accommodate screws or bolts. Bracket finishes can match their handrails. The bracket is attached to the handrail via the bracket&#39;s attachment head. This rail attachment head has the following characteristics: insertable into the handrail&#39;s channel at any point, twisted a quarter turn, and remain securely attached to the handrail. In another embodiment of the present invention, the rail attachment head has a through-hole (not shown), and once the rail attachment head has been securely fastened to the handrail, a fixing screw can be inserted through the through-hole, and screwed into the handrail&#39;s stress-relief channel for additional holding power. 
         [0015]    Wall Attachment Portions: Screws or bolts will be supplied by the user or the installer to suit any wall construction; these will be secured through pre-formed holes in the wall attachment portions. It will be recommended that these fasteners will be of steel, galvanized or otherwise coated to minimize risk of rusting, of gauge and length required to reach and penetrate solid portions of the wall, either into or through wood or metal studs, or solid masonry, or other materials capable of permanently sustaining the anticipated stresses. These fasteners are readily available in a great variety of configurations, and their supply and installation are not the responsibility of the manufacturer or seller of the handrails. These elements are not part of the invention. 
         [0016]    Optional accessories, gaskets and end pieces: The longer lengths of handrails result in few or no intermediate joints; the simple connection of brackets to handrails reduces labor costs and minimizes disruption during the construction period. Should the distance of required railing along a wall exceed the maximum available handrail length, plastic or metal union joints can be inserted into the handrail&#39;s ends, thereby providing a continuous gripping surface, aesthetic qualities, and ensuring that handrail lengths are be aligned. The union joints do not function as structural support for a user&#39;s weight between handrails; structural support is provided via wall brackets at pre-determined distances. Such union joints can join linear or non-linear segments of the handrail. At terminal ends, handrails will be neatly closed off by end caps. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  shows the perspective view of Variant  1  assembly of the present invention&#39;s preferred embodiment. 
           [0018]      FIG. 2  shows the perspective view of Variant  2  assembly of the present invention&#39;s preferred embodiment. 
           [0019]      FIG. 3  shows the wall bracket of Variant  1 . 
           [0020]      FIG. 4  shows the wall bracket of Variant  2 . 
           [0021]      FIG. 5  shows the cross-section of the railing of the preferred embodiment. 
           [0022]      FIG. 6  shows the top view of the geometry of Variant  2 &#39;s attachment head. 
           [0023]      FIG. 7  shows the perspective view of the Variant  2  bracket&#39;s attachment head. 
           [0024]      FIG. 8  shows a cross-section of assembly of Variant  2  in use. 
           [0025]      FIG. 9  shows an end cap. 
           [0026]      FIG. 10  shows the union joint of installed into one railing. 
           [0027]      FIG. 11  shows a railing with an end cap. 
           [0028]      FIG. 12  shows two lengths of railing joined by a union joint. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0029]    The present invention can be represented in many different variants. However, the essence of this invention resides in its ability to provide a stable handrail in almost any setting, providing there is a wall. The following two variants of the preferred embodiment are based on the objective to reduce manufacturing costs yet provide a product that can bear the weight of an average person. 
         [0030]    Referring now to figures,  FIG. 1  shows Variant  1  of the present invention. This variant comprises assembly  10 , consisting of bracket  12  and railing  16 .  FIG. 2  shows Variant  2 , comprising assembly  11 , consisting of bracket  14  and railing  16 . 
         [0031]      FIG. 3  shows the bracket  12  of Variant  1 , comprising wall support portion  19 , handrail attachment means or head  26  comprising rounded corner or tongue element  30  and ears  36 , and handrail support means  21  comprising of horizontal support arm  40  and vertical support arm  41 . Wall support portion  19  comprises two holes  23 ; support arm  40  extends horizontally from wall support portion  19  at substantially a 90° angle, and vertical arm  41  extends vertically from support arm  40  also at substantially a 90° angle. At the top of vertical post  41 , head  26  bends at substantially horizontally 90° and comprises rounded corner or tongue  30  on one end and ears  36  on the other end. In this preferred embodiment, tongue  30  is oriented to extend substantially away from wall support portion  19 ; however, it is possible to have ears  36  extend rather than tongue  30 . Ears  36  serve the purpose of supporting teeth  37  and orienting vertical arm  41  so that it does not interfere with installation inside T-shaped upper channel  17  as seen on  FIG. 5 . Teeth  37  function as frictionally immobilizing elements when head  26  is twisted into locked position inside the upper portion of T-shaped channel  17 . 
         [0032]    Referring to  FIG. 4 , bracket  14  of Variant  2  comprises wall support portion  24  with holes  25 , a handrail support means  22  comprising of horizontal support arm  42  and vertical support arm  43 , wherein support arm  42  extends outwardly from wall support portion  24 , and vertical arm  43  extending upwardly at substantially 90° from said support arm  42 . Handrail attachment means or head  28  bends horizontally at substantially 90° from vertical post  43 . Head portion  28  or tongue comprises two ends, one end has a square corner  35  and corner  32  having a rounded configuration, and the other end is provided with teeth  34 . Teeth  34  are located on the opposite side of rounded corner  32  and square corner  35 , and function as frictionally immobilizing elements when head  28  is rotated into locked position inside the upper portion  17  of T-shaped channel. Bend relief slots  38  are formed between vertical support arm  43  and square corner  35 , and between vertical support arm  43  and one of the teeth  34 . It is possible to make bracket  14  without bend relief slots  38 . Bracket  14  differs from bracket  12  in the fact that support arm  42  and vertical arm  43  are not oriented in the same plane as wall attachment portion  24 , and lie in the same plane with respect to each other. The characteristic of the design of bracket  14  is that horizontal support arm  42  (shown on  FIG. 4 ) is much more resistant to vertical displacement than horizontal support arm  40  (shown on  FIG. 3 ) due to its vertical rather than horizontal orientation of support arm  40 . Support arm  40  is more adept at resisting horizontal force, but it is also more prone to bend out of shape. Support arm  42  is less resistant to horizontal displacement, but can hold more weight before failing. 
         [0033]    It is important to note that many different configurations of the bracket are envisaged, from cast metal to bent sheet metal to molded plastic. Unlimited combinations. and profiles of wall attachment portion  24 , horizontal support arm  40 , and vertical post  43  may be employed by those skilled in the art to achieve the desired characteristics of strength, aesthetic appeal, and ease of attachment to the wall. The most important element of the present invention is the interaction between lower  18  and upper 17 portions of T-shaped channel and a bracket&#39;s head  28 . 
         [0034]      FIG. 5  shows a cross-section of handrail  16 , comprising lower portion of T-shaped channel  18 , upper portion of T-shaped channel  17  and stress relief channel  20 . Stress-relief channel  20  permits handrail  16  to flex slightly outwardly during installation of rail attachment head  26  or  28 . It also serves to assist joining two railings  16  end-to-end, namely as a cavity to accommodate a fixing screw (not shown) for union joint  52  of  FIG. 10 . Railing  16  can be manufactured by aluminum extrusion, or of any other material.  FIG. 5  also shows the geometric relationship of the T-shaped channel&#39;s lower and upper portions  18  and  17  respectively: for the invention to work properly, lower portion  18 , or “N”, is narrower than the upper portion  17 , or “W 1 ”. “N” must be at least 50% and no more than 95% of “W 1 ”. In practice, the ratio should be in the range of 70% to 90%. In the preferred embodiment this ratio is approximately 80%. 
         [0035]      FIG. 6  demonstrates the geometric relationship of Variant  2  bracket&#39;s head  28 : length “L” must be substantially the same size as the width of the T-shaped channel&#39;s lower portion  18 , “N”, of  FIG. 5 , and “W 2 ” must be substantially the same size as the width of T-shaped channel&#39;s upper portion  17 , “W 1 ”, of  FIG. 5 . This way, head  28  can be inserted into the lower portion  18  at any point, lifted into upper portion  17 , twisted 90°, and thus remain in place, considering that the width “W 1 ” in the T-shaped channel&#39;s upper portion  17  and the width “W 2 ” of head  28  are substantially identical. 
         [0036]      FIG. 7  shows Variant  2  bracket&#39;s head  28  comprising teeth  34  to cooperate with the inside walls of T-shaped channel&#39;s upper portion  17  in order to snugly immobilize said head  28  within said upper portion  17 . 
         [0037]      FIG. 8  shows a cross-section of Variant  2 , comprising railing  16  attached to bracket  14 , which is affixed by screws  48  to a wall  46 &#39;s stud  44 . This is a typical installation of assembly  11  to provide assured support to a user along a wall. 
         [0038]      FIG. 9  shows the end cap  50 . A U-shaped recess  54  (can also be a formed through-hole) accommodates a fixing screw (not shown) that passes through said recess  54  and into stress relief channel  20  of handrail  16 . Once a fixing screw is tightened through said recess  54 , end cap  50  is immobilized within an extremity of handrail  16 . 
         [0039]      FIG. 10  shows the union joint  52  within handrail  16 . Union joint  52 &#39;s configuration is similar to end cap  50 , with the exception that it is mirrored on both sides. Union joint  52  also comprises a U-shaped recess  56  (can also be a formed through-hole) to accommodate a fixing screw (not shown) that is affixed within stress relief channel  20  of handrail  16 . 
         [0040]      FIG. 11  shows handrail  16  capped off with end cap  50 . End cap  50  slides into the extremity of handrail  16 , and serves an aesthetic and hygienic purpose.  FIG. 12  shows two handrails  16  connected together with a union joint  52 . Once joined, both handrails  16  provide a smooth, continuous surface for user&#39;s hands; such a joint is also aesthetically pleasing. In another embodiment (not shown), said union joint  52  is of a configuration to be completely shielded from view by handrails  16 , thus providing a continuous, uninterrupted surface. Extremities of handrails  16  would simply meet at a seam, with the union joint  52  being invisible to the eye. 
         [0041]    In operation (for brevity, we will use Variant  2  and a stud-retained wall), referring now to all Figures, the user will determine mounting locations in wall  46 , preferably into a stud  44 . Indicia (not shown) are marked on railing  16  to align attachment locations of wall support portion  24  with said stud  44 . User inserts bracket  14 &#39;s head  28  into railing  16 &#39;s T-shaped channel&#39;s lower portion  18  in such a way that head  28 &#39;s length “L” spans across the T-shaped channel&#39;s lower portion  18  width “N”. Considering that “L” is approximately the same width as T-shaped channel&#39;s lower portion  18 , “N”, head  28  is insertable into the spot marked by indicia. User lifts or slides head  28  into the T-shaped channel&#39;s upper portion  17  and rotates bracket  14  substantially 90° in such a way that rounded corner  32  abuts a wall of upper portion  17  and facilitates a turning motion of head  28  inside T-shaped channel&#39;s upper portion  17 , or “W”. Teeth  34  are forced into the opposite wall of upper portion  17 , locking head  28  inside said upper portion  17 . Head  28  therein acts as a cam, wherein the 90° rotational movement of head  28  is translated into lateral immobilization of head  28  within upper portion  17  by the engagement of teeth  34  on one wall and square corner  35  on the opposite wall of the upper portion  17 . 
         [0042]    Considering that head  28 &#39;s width “W” is substantially identical to the width of upper portion of T-shaped channel  17 , “W”, it snugly locks into place. Teeth  34  provide an additional means of immobilization of head  28  inside railing  16 ; teeth  34  dig into the walls of the T-shaped channel&#39;s upper portion  17 . If the user makes a mistake, it is possible to undo this immobilization by reversing the procedure and moving head  28  to a different location inside upper portion  17 . Presumably, user will orient all brackets  14  in the same direction. 
         [0043]    Once the user is satisfied by the placement of bracket  14 , assembly  11  can be mounted to wall  46  via screws  48  and holes  25 . Once the assembly  11  is attached to wall  46 , user can either seal off the end of railing  16  with an end cap  50  or install additional assemblies  10  to provide a continuous wall railing. As mentioned, railings  16  can be joined via a union joint  52 . Union joint  52  can join linear and non-linear assembly  10  or  11  configurations. For example, if two walls meet at an angle, union joints  52  can be precisely made to join two handrails  16  for a continuous and uninterrupted handrail assembly  10  or  11 . 
         [0044]    The present invention is not limited to merely hallway and room walls. It can easily adapt to staircases: user simply bends rail attachment means  28  to or away from vertical arm  43  to accommodate a railing  16  that follows the incline of the staircase (not shown). 
         [0045]    Interior and exterior walls may be classified as follows: 
         [0000]    1. Walls with finishes [i.e. gypsumboard, lath and plaster, wallboards of all types] are supported on vertical wood or metal studs, known as frame construction, spaced to suit structural requirements or characteristics of the finishing materials. The studs are concealed behind these materials and their spacing is not usually visible. It is necessary to determine where the studs are by using stud locators or by drilling exploratory holes so that brackets could twisted into the handrails to match the locations of the studs.
 
2. Walls built of solid materials [i.e. brick, concrete masonry, cast concrete, stone] may have finishes applied directly over their surfaces. If wall finishes noted above are applied over wood or metal furrings that provide a space between them and the solid backing, the spacing of these furrings is usually not apparent, and their location must be determined in the same manner as studs.
 
         [0046]    Handrails that are secured to any wall must be anchored directly to solid materials described above or to studs or furrings. As noted above, it is necessary to locate these members before handrail brackets are anchored. Handrails or bars designed with brackets already fixed in place often are anchored wholly or partially to finishes that may not be substantial or that will deteriorate in use. Otherwise handrails must be custom-built so they can be anchored directly to studs or furrings. Some systems permit random spacing of brackets using fasteners of different sorts but this invention allows the brackets to be quickly twisted into place at locations that will provide permanent, solid bearing without any additional fasteners. 
         [0047]    The system is designed to conform to current building codes in Canada and the United States; their requirements ensure that the handrails are capable of being solidly gripped, and of sustaining stresses of their users. 
         [0000]    Advantages of this Invention 
         [0048]    Simplicity: The system has two components: the handrail and the bracket. The bracket can be readily twisted into the extruded channel of the handrail at any point along its length. Once the locations of the studs are determined, the brackets are attached to the handrail and the entire assembly is secured to the wall using standard screws consistent with the type and position of the studs. On solid walls, the brackets are located to support the handrails at intervals determined by the structural characteristics of the handrail; suitable limitations are recommended in instructions furnished to users. 
         [0049]    Flexibility: The handrails are made of aluminum extrusions that present a continuous slot allowing the bracket to be twisted securely in place, or removed by reverse-twisting if circumstances require. The extrusions will be of lengths allowing them to be installed in large rooms and long hallways without joints. The system can be installed sloped [parallel to stairways or ramps] or horizontal [parallel to floors]. 
         [0050]    Cost advantages: Because handrails can be easily cut to length and brackets can be rapidly installed wherever needed or desired, labor costs are substantially reduced and disruption of users&#39; facilities is minimized. Although this system can readily be installed by any competent workman, it is recommended that carpenters familiar with characteristics of wall construction install or verify the installation of the handrails. 
         [0051]    Marketing: The handrails can be cut to length and sold through retail establishments; sales ‘by the foot’ will appeal to the ‘do it yourself’ market, thereby improving safety of their occupancies. This product can also be sold and installed through commercial supply depots, contractors and any other distribution chain of supply. The finished assembly  10  or  11  of the present invention is no less attractive than custom-welded and modular systems currently available on the market, at a fraction of the cost. 
         [0052]    Appearance: The simple tubular handrail profile is unobtrusive and projects from walls only enough to permit the handrails to be comfortably gripped by users and allows hands to slide without obstruction to their movement. The attachment heads of the brackets are completely hidden from view within the handrail profile, providing an integrated appearance and resistance to tampering similar to that of custom-welded handrail systems of much higher cost. 
         [0053]    Advantages to users: The variable lengths of handrails result in few or no intermediate joints; the simple connection of brackets to handrails reduces labor costs and minimizes disruption during the construction period.

Summary:
This invention relates to a handrail assembly that can be installed on any wall. The assembly consists of a handrail and a bracket. The bracket can be twist-locked inside the handrail at any point in the handrail because the handrail has a continuous T-shaped channel at the bottom. The T-shaped channel&#39;s bottom portion is narrower than the upper portion. The bracket has a head that is as wide as the T-shaped channel&#39;s bottom portion and as long as the T-shaped channel&#39;s upper portion. The head has one curved corner to facilitate turning and teeth to bite into the upper portion of the channel&#39;s wall. The head is lifted through the bottom portion into the upper portion of the channel, the bracket is rotated a quarter turn, and the bracket becomes immobilized. The head of the bracket acts as a cam. Union joints can join multiple lengths of handrails.