Abstract:
A telescoping, retractable handrail for a recreational vehicle automatically extends or retracts when the retractable stairs of the vehicle are extended or retracted. The handrail contains an upper rail pivotally attached at one end to the outer wall of the vehicle and a lower rail pivotally attached at one end to the stairs of the vehicle. The unattached ends of both rails are telescopingly engaged with one another. Preferably, the lower rail telescopes within the upper rail. When the stairs are extended, the lower rail moves downward and outward to extend the rail for use by a person entering the vehicle. The handrail may also contain upper and lower brackets for pivotally attaching the upper and lower rails to the wall and stairs, respectively.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 60/165,909 filed Nov. 16, 1999, which is herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to handrails for stairs and steps. More particularly, it relates to a retractable handrail for use with retractable stairs on recreational vehicles and the like. 
     BACKGROUND ART 
     A large segment of the American population owns motor homes, recreational vehicles (RVs), travel trailers, or fifth wheel trailers. These vehicles typically contain side doors located a substantial distance from the ground, with retractable stairs containing two or three steps for entry through the door. The stairs fold underneath the vehicle for travel and are either manually or automatically extended when the vehicle is parked. By their nature, retractable stairs are rather unstable, projecting from the side of the vehicle and providing no lateral support for a person entering the vehicle. A need for a handrail to accompany retractable stairs on recreational vehicles has long been recognized in the art, and numerous designs have been proposed. However, many recreational vehicles are currently sold without handrails, indicating that none of the existing designs are both cost-effective and technically suitable. 
     Most of the handrails found in the art suffer from two main disadvantages: mechanical complexity and manual extension. A foldable handrail structure is disclosed in U.S. Pat. No. 4,261,550, issued to Gregory. A hollow handrail is connected at one end to a bracket attached to the RV wall. Within the handrail moves a first end of a slide whose second end is connected to a second wall bracket located below the first. The slide moves along the handrail, extending the handrail away from the wall when the slide is at the lower end of the handrail, and folding the handrail toward the wall when the slide moves to the upper end of the handrail. The handrail structure of Gregory must be opened and closed manually, making it awkward to adjust. 
     A foldable hand rail is disclosed in U.S. Pat. No. 4,029,352, issued to Evans. The hand rail swings away from the camper wall during use and is supported by a strut that extends laterally from the rail. The strut helps to stabilize the hand rail and limit its lateral movement. The hand rail of Evans must be extended manually and is quite mechanically complex, introducing a higher possibility of part malfunction or breakage. 
     A cantilevered, retractable handrail is disclosed in U.S. Pat. No. 5,116,025, issued to Kiniry. The handrail requires no support post and pivots around its top end to be positioned against the wall or extending away from the wall. As with the rails of Gregory and Evans, the handrail of Kiniry must be manually extended and retracted. It also requires a complicated hinge that can support the handrail in its extended position without requiring a support post. 
     A foldable handrail assembly is disclosed in U.S. Pat. No. 5,024,420, issued to Downing. The assembly is similar to handrail of Gregory, but contains an additional stabilizer rod. Most importantly, the assembly allows varying placement of its parts to facilitate retrofitting of different designs of trailers. The handrail of Downing is mechanically complex and requires manual retraction. 
     A storable stairway and platform apparatus for recreational vehicles is disclosed in U.S. Pat. No. 4,720,116, issued to Williams et al. The stairway has scissor linkages for folding the steps into parallel alignment with each other for retraction. The stairway may also be supplied with a foldable banister that is removably attached to a bracket on the RV wall. In order to retract the banister, a pin must be removed from the bracket and the banister folded away from the wall. The banister must be manually removed from and attached to the wall when desired. 
     There is a need, therefore, for an improved handrail for a recreational vehicle that is mechanically simple, can be added to existing vehicles, and automatically retracts and extends with the stairs. 
     Objects and Advantages 
     Accordingly, it is a primary object of the present invention to provide a telescoping handrail that automatically retracts or extends when the stairs of the recreational vehicle are retracted or extended. 
     It is a further object of the invention to provide a retractable handrail that is mechanically simple and contains few parts, reducing the frequency of necessary maintenance or repair. 
     It is an additional object of the invention to provide a handrail for recreational vehicles that can easily be added to existing vehicles. 
     It is another object of the present invention to provide a strong, durable handrail that provides sufficient support while remaining lightweight. 
     It is a further object of the invention to provide a retractable handrail that is aesthetically appealing, providing a clean, uncluttered look to the outside of the recreational vehicle. 
     It is an additional object of the invention to provide a retractable handrail that is compact and projects only a few inches from the side of the vehicle when in its retracted position. 
     Finally, it is an object of the invention to provide a retractable handrail that is inexpensive to manufacture and to purchase. 
     SUMMARY 
     These objects and advantages are attained by a retractable handrail for a recreational vehicle (RV) that contains retractable stairs for entry through a door. Extending the stairs causes extension of the handrail, and retraction of the stairs causes retraction of the handrail. The handrail contains an extended upper rail, between two and five feet long, and an extended lower rail, between two and three feet long. The upper rail has a wall end that can be pivotally attached to an outer wall of the vehicle, adjacent to the door, and a bottom end telescopingly engaged with a top end of the lower rail. The lower rail also has a step end that can be pivotally attached to the stairs. Preferably, the lower rail telescopes within the upper rail, but the upper rail may instead telescope within the lower rail. At least one spacer is preferably secured around the lower rail at a location that remains within the upper rail during extension and retraction of the handrail. When the stairs are extended, the lower rail travels in an outward and downward direction, sliding within the upper rail and extending the handrail. Preferably, the handrail is made of metal, and most preferably of steel. 
     When the handrail is attached to the RV wall and retracted, the step end of the lower rail and the wall end of the upper rail are substantially vertically aligned, and the handrail extends at most six inches from the outer wall of the RV. Preferably, the upper rail is bent to form an obtuse angle, approximately 150°, near the wall end. The angle defines a rail plane, and the handrail is positioned so that the rail plane is perpendicular to the outer wall. The upper and lower rails are preferably both tubular with circular cross section. The upper rail may be connected to the RV via an upper bracket fixed to the outer wall. Similarly, the lower rail may be connected to the RV via a lower bracket fixed to the stairs, either to the side or bottom of the lowest step. The rails are pivotally connected to their respective brackets. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIGS. 1A-1B illustrate a preferred embodiment of the handrail of the present invention in its retracted and extended positions. 
     FIGS. 2A-2B show two parts of the upper rail of the handrail of FIGS  1 A- 12 B. 
     FIG. 3 shows the lower rail of the handrail of FIGS. 1A-1B. 
     FIG. 4 illustrates schematically one embodiment of an upper bracket of the present invention mounted to an RV. 
     FIGS. 5A-5D are left, right, front, and top plan views, respectively, of the upper bracket of FIG.  4 . 
     FIGS. 6A-6B are left and front plan views, respectively, of an alternative embodiment of an upper bracket of the present invention. 
     FIG. 7 is a cross-sectional view of the side mount embodiment of the lower bracket of the present invention. 
     FIG. 8 is a front perspective view of the side mount bracket of the present invention. 
     FIG. 9 is a front perspective view of a spacer used in the side mount embodiment of FIG.  7 . 
     FIG. 10 is a side perspective view of a bearing used in the side mount embodiment of FIG.  7 . 
     FIG. 11 is a cross-sectional view of the tread mount embodiment of the lower bracket of the present invention. 
     FIG. 12 is a side perspective view of the tread mount bracket of the present invention. 
    
    
     DETAILED DESCRIPTION 
     Although the following detailed description contains many specifics for the purposes of illustration, anyone of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the following preferred embodiment of the invention is set forth without any loss of generality to, and without imposing limitations upon, the claimed invention. 
     The present invention provides a retractable, telescoping handrail for use with a recreational vehicle (RV). As used herein, a recreational vehicle includes any vehicle having retractable stairs for entry into a door, such as a motor home, travel trailer, and fifth wheel trailer. The steps retract for traveling and extend for access to the interior when the vehicle is parked. The present invention may be used with both manually and automatically retractable stairs, and extends or retracts automatically when the stairs are extended or retracted. When the handrail is retracted, it extends only a short distance, such as six inches, from the side of the vehicle. The total width of the vehicle therefore remains within the legal limits for travel. 
     A preferred embodiment of the handrail  10  of the present invention is shown in FIGS. 1A and 1B. FIG. 1A illustrates handrail  10  in its retracted position, and FIG. 1B illustrates handrail  10  in its extended position. Handrail  10  is fixed to the outer wall  12  of a recreational vehicle, adjacent to the doorway  14 . Below doorway  14  is a set of retractable stairs  16 , shown in a retracted position in FIG.  1 A and an extended position in FIG.  1 B. Stairs  16  are shown having two steps, but they may have any number of steps. Handrail  10  contains an extended upper rail  18  and an extended lower rail  20  that are telescopingly engaged. Upper rail  18  has a wall end  22  that is pivotally attached to wall  12  and a bottom end  24 . Lower rail  20  has a top end  26  and a step end  28  that is pivotally attached to stairs  16 . Bottom end  24  of upper rail  18  is telescopingly engaged with top end  26  of lower rail  20 . Preferably, lower rail  20  travels within upper rail  18 , as indicated by the dotted lines illustrating the portion of lower rail  20  that is inside upper rail  18 . However, upper rail  18  may instead travel within lower rail  20 . Of course, the relative diameters of the two rails depend upon which travels within the other. 
     When stairs  16  are extended, handrail  10  pivots away from wall  12  at wall end  22  of upper rail  18 . Upper rail  18  and lower rail  20  move away from each other in a telescoping fashion to increase the total length of handrail  10 , as illustrated in FIG.  1 B. Handrail  10  is preferably mounted so that step end  28  of lower rail  20  is in substantial vertical alignment with wall end  22  of upper rail  18  when handrail  10  is in a retracted position. The substantial vertical alignment is such that no significant lateral forces are applied to any part of handrail  10  white it is being extended. 
     Upper rail  18  is illustrated in more detail in FIGS. 2A and 2B. Upper rail  18  is preferably formed of mild steel tubing with a circular cross section. Preferably, the mild steel tubing has a powder coated stipple finish on its entire outer surface to provide a non-slip grip. However, upper rail  18  may also be made of stainless steel, aluminum, or other metal; plastic; or any other suitable material. Located near wall end  22  is a bend  30  that forms an obtuse angle  32  in upper rail  18 . Obtuse angle  32  is preferably approximately 150°, but it may range between 90° and 180°. Referring again to FIG. 1B, note that angle  32 , the location of bend  30 , and distances  34  and  36  determine the angle  38  that the majority of handrail  10  makes with a lower step  40  of stairs  16 . Angle  32  is preferably chosen to provide a comfortable angle  38  and distance  36  while using the minimum amount of material and keeping handrail  10  sufficiently separated from wall  12  when retracted. Bend  30  defines a rail plane containing angle  32 , i.e., the plane of the paper of FIG.  2 A. This rail plane is preferably perpendicular to wall  12  for the most comfortable use of handrail  10 . 
     FIG. 2B illustrates an endpiece  42  that is inserted into wall end  22  of upper rail  18  to facilitate attachment to a wall bracket. A round part  44  has a circular cross section (or the same shaped cross section as wall end  22 ) and is inserted into wall end  22  of upper rail  18 . Round part  44  has an outer diameter that is slightly smaller than the outer diameter of upper rail  18 , so that it can fit snugly within upper rail  18 . A flattened part  46  tapers from a circular cross section at location  48  to a flat region  50  that contains a hole  52 . A bolt may be inserted through hole  52  to attach wall end  22  of upper rail  18  in a pivotal manner to wall  12  of the RV. When an upper bracket of the present invention (described below) is used, endpiece  42  is inserted into wall end  22  such that flat region  50  is parallel to the rail plane defined by bend  30 . 
     Lower rail  20  is illustrated in more detail in FIG.  3 . Lower rail  20  is preferably formed of stainless steel tubing that has a circular cross section. However, it may also be made of aluminum or other metal, plastic, or any other suitable materials. Step end  28  is preferably flattened and contains a hole  54  through which a bearing may be inserted. Step end  28  may be attached to stairs  16  in a pivotal manner via a bolt through this bearing and hole  54 . While lower rail  20  is shown straight, it may have any bends deemed necessary and still remain within the scope of the present invention. 
     As shown in FIGS. 1A and 1B, the preferred embodiment of handrail  10  has lower rail  20  sliding in a telescoping manner within upper rail  18 . Lower rail  20  therefore has a smaller outer diameter than does upper rail  18 . In addition, lower rail  20  contains optional spacers or bearings  56  and  58  that are tubular and fit around lower rail  20 . Spacers  56  and  58  provide a snug, evenly spaced fit between lower rail  20  and upper rail  18  during extension and retraction of handrail  10 . They also provide for smooth (i.e., low friction) extension and retraction of handrail  10 . Spacers  56  and  58  may be made of any suitable material such as plastic and are strongly secured to lower rail  20  by any suitable method. For example, spacers  56  and  58  may be cut from lengths of polyvinyl chloride (PVC) pipe and glued in place. Spacer  58  is preferably located directly adjacent to top end  26 . Spacer  58  may also be located within a few inches of top end  26 . Spacer  56  is separated from spacer  58  by a distance  61  such as twelve inches. Both spacers  56  and  58  are located so that when handrail  10  is in its extended position, the portion of lower rail  20  containing spacers  56  and  58  remains inside upper rail  18 . That is, spacers  56  and  58  remain inside upper rail  20  at all times. While FIG. 3 illustrates two spacers, it is to be understood that any number of spacers may be used. Of course, if upper rail  18  instead slides within lower rail  20 , then spacers are instead secured around upper rail  18 . 
     Note that while it is preferred that both upper rail  18  and lower rail  20  are made of tubular materials, it is not required. Tubular materials are in general less expensive and easier to machine. However, only the rail that is serving as the outer rail, upper rail  18  in the preferred embodiment, must be tubular. The other rail, lower rail  20  in the preferred embodiment, may be solid. Furthermore, only the length of the outer rail in which the inner rail travels must be tubular. The remainder of the outer rail may be solid. 
     Typical dimensions of upper rail  18  are a total length (i.e., before bend  30  is created) of between two and five feet, such as 28, 42, or 48 inches. A typical outer diameter is 1¼ inches with a wall thickness of 0.065 inch. The radius of curvature of bend  30  may be approximately three inches. Typical dimensions of lower rail  20  are between two and three feet, such as thirty inches. A typical outer diameter of lower rail  20  is one inch with a wall thickness of 0.065 inch. Spacers  56  and  58  are typically separated by about twelve inches. 
     While these are preferred dimensions, any suitable dimensions are within the scope of the present invention. It may be desirable to manufacture the handrail in varying lengths to accommodate different heights of users, or to manufacture custom handrails according to a user&#39;s specifications. The handrail may be treated with special coatings, such as a rustprevention coating, if desired. 
     The location on wall  12  at which upper rail  18  is pivotally attached, i.e., the value of distance  36 , may vary as desired. Motor homes often have a grab handle adjacent to the door. If an existing motor home is being retrofitted with handrail  10 , then the grab handle can be removed and replaced with a bracket for pivotally mounting upper rail  18 . In this case, the bracket can be mounted at the height of either the top or bottom (or an intermediate location) of the replaced grab handle. Upper rails of lengths 48 or 42 inches, respectively, have been found to work particularly well with such bracket placement. Alternatively, upper rail  18  can be pivotally attached below the existing grab handle. In this case, and upper rail length of  28  inches has been found to work particularly well. 
     Any suitable upper bracket may be used to pivotally attach wall end  22  of upper rail  18  to wall  12 . A preferred bracket  60  of the present invention is illustrated schematically in FIG.  4  and in more detail in FIGS. 5A-5D, which show left plan, right plan, front plan, and top plan views, respectively. Bracket  60  is designed specifically to attach to existing vehicles without requiring any changes to the door or door jamb. Bracket  60  may be made of any suitable material; for example, it may be cast aluminum. FIG. 4 is a top sectional view of an RV wall to which top bracket  60  has been attached. Shown are an interior RV wall panel  62 , an exterior RV skin  64 , and a typical door jamb  66 . Bracket  60  fits around door jamb  66  as shown. Bracket  60  contains two leaves, a left leaf  68  and a right leaf  70 , that create a slot  72 . Region  50  of endpiece  42  (FIG. 2B) is inserted into slot  72  and secured with a bolt that passes through hole  52  and through holes in each of left leaf  68  and right leaf  70 . This connection creates the pivotal motion required for operation of handrail  10 . 
     Turning now to FIGS. 5A-5D, FIG. 5A shows the left side of bracket  60 . Left leaf  68  contains a hole  74  through which a bolt is passed to pivotally secure endpiece  42  to bracket  60 . Also shown are two holes  76  and  78  through which bolts are inserted to attach bracket  60  to the outer wall of the RV. Note that the left side of left leaf  68  is preferably flush with the left side of the entire bracket  60 . FIG. 5B is a right view of bracket  60 , showing the right side of right leaf  70 . The bolt passing through hole  74  and endpiece  42  also passes through a hole  80  in right leaf  70 . Bolts are also inserted through holes  82  and  84  to secure bracket  60  to door jamb  66 . Note that the right side of right leaf  70  is not flush with the right side of the entire bracket, to accommodate door jamb  66 . FIG. 5C is a front view of bracket  60  showing the locations of left leaf  68 , right leaf  70 , slot  72 , and holes  76 ,  78 ,  82 , and  84 . FIG. 5D is a top view of bracket  60  showing left leaf  68 , right leaf  70 , slot  72 , and holes  74 ,  80 ,  78 , and  84 . A portion  85  of bracket  60  fits around door jamb  66  as shown in FIG. 4, allowing mounting screws to penetrate the door framing member and provide an extremely secure attachment of bracket  60  to wall  12 . 
     An alternative embodiment of an upper bracket  71  is shown in FIGS. 6A and 6B, left and front plan views, respectively. Upper bracket  71  mounts flat on RV outer wall  12  and is used when the RV door jamb is of a different style than door jamb  66 . Bracket  71  may be made of any suitable material; for example, it may be cast aluminum. Bracket  71  contains two symmetric leaves  73   a  and  73   b  that define a slot  75  into which region  50  of endpiece  42  (FIG. 2B) is inserted. A bolt passes through hole  52  and through holes  77   a  and  77   b  in leaves  73   a  and  73   b  to create the pivotal connection required for operation of handrail  10 . Bracket  71  can be mounted to the RV wall with screws passing through holes  79   a  and  79   b  and into either the wall itself or sex bolts that pass through the entire wall thickness, exposing their heads on the interior wall surface. 
     Any suitable lower bracket may be used to pivotally attach step end  28  of lower rail  20  to stairs  16 . The lower bracket must also extend the attachment point beyond the front of the stairs to ensure that handrail  10  does not contact the RV wall during retraction. The present invention provides two lower bracket embodiments: a side mount embodiment and a tread mount embodiment. The side mount embodiment is generally preferred; however, some RV steps have a slot in the side that is necessary for operation of the stairs, and the side mount embodiment would interfere with such operation. In this case, the tread mount embodiment is employed. The side mount embodiment is illustrated in FIG. 7, along with upper rail  18  and lower rail  20 . Also shown in cross section is an RV step  90 . Typically, RV step  90 , which is the lowest step of the stairs, contains a tread portion  92 , a side lip  94 , and a front lip (not shown). The front lip extends down from tread  92  in a manner similar to the one in which side lip  94  extends down. A side mount bracket  96 , shown in FIG. 8, extends forward from side lip  94 , with its front end  114  directed toward the front of the stairs. The edge of front end  114  of side mount bracket  96  is visible in FIG. 7. A carriage bolt  98  extends through bracket  96 , a spacer  100 , a jam nut  101 , and two bearings  102  and  104  that are inserted into hole  54  of lower rail  20 . Carriage bolt  98  is then secured with a lock nut  106  that preferably contains a nylon insert. Spacer  100  is shown in perspective view in FIG.  9 . Spacer  100  determines how far away from the stairs lower rail  20  is positioned, and may be of any length needed to provide vertical alignment between wall end  22  of upper rail  18  and step end  28  of lower rail  20 . A suitable length is 1¾ inches. Bearings  102  and  104 , illustrated in FIG. 10, are preferably bronze and extend fully into hole  54  of lower rail  20 . Bearings  102  and  104  provide smooth pivoting of lower rail  20  with respect to carriage bolt  98 . 
     Referring again to FIG. 8, side mount bracket  96  contains three holes  108 ,  110 , and  112 . Holes  108  and  110  fit carriage bolts that secure side mount bracket  96  to side lip  94  of step  90 . Carriage bolt  98  is inserted through hole  112 . Side mount bracket  96  serves simply to extend the position of bolt  98  beyond the front of step  90 , thus ensuring that lower rail  20  does not contact the wall of the RV when handrail  10  is in its retracted position. Side mount bracket  96  may be made of a flat steel bar. A typical length of side mount bracket  96  is between five and seven inches. Front end  114  of side mount bracket  96  is preferably rounded and smooth, so that any inadvertent contact with side mount bracket  96  by a user is relatively safe. 
     The tread mount embodiment of the lower bracket is illustrated in FIG. 11, along with upper rail  18  and lower rail  20 . In the tread mount embodiment, the lower bracket is attached to the bottom of the lowest step of the stairs. Also shown in cross section is an RV step  120 . Typically, RV step  120 , which is the lowest step of the stairs, contains a tread portion  122 , a side lip  124 , and a front lip (not shown). The front lip extends down from tread  122  in a manner similar to the one in which side lip  124  extends down. A tread mount bracket  126 , shown in FIG. 12, extends from tread  122 . Tread mount bracket  126  contains a tread portion  128 , a sloped portion  130 , a twisted portion  132 , and a front edge  134 . Each portion is labeled in FIG.  11 . Tread mount bracket  126  serves a similar purpose as side mount bracket  96 : it pivotally secures lower rail  20  to step  120  and extends the point of securing away from the RV. Tread mount bracket  126  can be made of a flat steel bar. Bolts  142  inserted through holes  136  and  138  secure tread mount bracket  126  to tread  122 . 
     Referring again to FIG. 11, a carriage bolt  144  is inserted through a hole  140  in tread mount bracket  126 , and then through a spacer  146 , a jam nut  147 , and two bearings  148  and  150 . Bearings  148  and  150  are preferably bronze and are inserted into hole  54  of lower rail  20 . As in the side mount embodiment, bearings  148  and  150  provide for smooth rotation of lower rail  20  with respect to carriage bolt  144 . Bolt  144  is secured by lock nuts  152  and  154 . Lock nut  154  preferably also contains a nylon insert. Spacer  146  is similar to spacer  100  of FIG. 9, but is typically longer, such as 2½ inches, in order to provide vertical alignment between wall end  22  of upper rail  18  and step end  28  of lower rail  20 . 
     It will be clear to one skilled in the art that the above embodiment may be altered in many ways without departing from the scope of the invention. For example, different upper and lower brackets may be used to pivotally secure handrail  10  to the vehicle. Handrail  10  may be advantageously manufactured from newly developed materials that are strong, lightweight, easy to machine, and attractive. Comfortable hand grips may be added to the outside surface of upper rail  18 . Accordingly, the scope of the invention should be determined by the following claims and their legal equivalents.