Abstract:
Walk through ladder extensions are provided to attach to the upper ends of ladder side rails, and define a wide unobstructed space between them. The extensions can be gripped by a user to steady the user as the user moves onto a roof of a building against which the ladder is placed.

Description:
[0001]     This application refers to and claims the benefit of priority from two U.S. Provisional Patent Applications, namely, Ser. No. 60/564,698, filed Apr. 23, 2004 and Ser. No. 60/605,606, filed Aug. 30, 2004 and both applications are hereby incorporated by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to hand grip or rail extensions that are placed onto the upper or top end of a ladder, and spaced apart sufficiently to permit a person or user to have hand grips above the upper end of the ladder, which can be used for support as a person or user walks between the hand grip or rail extensions onto a roof or other support structure. The extensions are fixed to the upper ends of the side rails of a ladder, and provide a pair of stable uprights of selected height. Suitable clamps, locks or attachment members can be utilized for securing the extensions to the ladder rails or to the rungs.  
         [0003]     When ladders are placed against the edge of a roof of a building, for example, many times the ladder upper end will be right at the edge of the roof, and no user, hand grip or support is provided. Even if the ladder protrudes above the roof, there is difficulty in getting onto the roof because of the interference of the ladder rungs. This makes it so the user may have to go around or to the outside of the ladder and step onto the roof, which can be hazardous.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention relates to a ladder walk through stabilizer extension assembly for an upper end of the ladder to provide a support for a person using a ladder as the person steps onto a roof or other surface at the top of the ladder. A pair of upwardly projecting extension rails or hand grips that are spaced apart can be used by a user moving from the ladder onto a roof or surface for a more stable support while doing so. There are no obstructions between the upright extension rails or supports, and thus, there is no interfering members that would form any obstructions when a person steps between the extensions. The upright extension rails extend above each of the side rails of the ladder. This means that the operator does not have to crawl on hands and knees or assume awkward positions to go around the side of the ladder, or move to clear rungs or other obstructions.  
         [0005]     The extension rails can be any desired form, but preferably mount directly on or against the side rails of the ladder, and then are clamped or fixed securely in place. The extensions also can be attached to upper ladder rungs, or with hollow rung ladder, the connections can be long bolts that extend through the rungs.  
         [0006]     The extension rails or supports are each preferably formed metal tubes that form an inverted U, so that one or both legs of the U, which extend upwardly from the ladder, can be gripped by a person. The upper end can be formed into a rounded, hand grip portion that is easily held as well. The extensions or rails preferably are made or formed so the “walk through” portions are spaced wider than the ladder rails to accommodate the user without interference as the person steps onto a support.  
         [0007]     The extensions make it easy to get onto a roof in particular, and also get off of a roof, without having to climb over rungs, or awkwardly attempt to go around the side of a ladder, at the same time when the user has to go on to a roof slope. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIG. 1  is a side view of an extension ladder having a walk through extensions made according to the present invention installed thereon;  
         [0009]      FIG. 2  is an enlarged view of a mounting arrangement for holding the walk through extensions on to the upper end of a ladder, with parts in section and parts broken away;  
         [0010]      FIG. 3  is a front view of the ladder of  FIG. 1 ;  
         [0011]      FIG. 4  is a sectional view taken as on line  4 - 4  in  FIG. 3 ;  
         [0012]      FIG. 5  is a fragmentary perspective view of the support for one of the walk through extensions made according to the present invention;  
         [0013]      FIG. 6  is a front view of a first modified second form of the present invention;  
         [0014]      FIG. 7  is an exploded view of a modified third form of the invention showing a walk through rail attachment that will be held on the top two rungs of a ladder;  
         [0015]      FIG. 8  is a vertical sectional view of the modified third form of the invention showing the walk through attachment mounted on the top two rungs of a ladder;  
         [0016]      FIG. 9  is an exploded view of a modified fourth form of the invention when used with a hollow rung ladder;  
         [0017]      FIG. 10  is a view of the first form of the invention modified to include holders for paint brushes or other tools on brackets that would receive walk through hand rails removable from base sections on the ladder, which base sections can be left on the ladder and used to support accessories;  
         [0018]      FIG. 11  is a perspective view of a further embodiment of the invention;  
         [0019]      FIG. 12  is a sectional view taken on line  12 - 12  in  FIG. 11 ; and  
         [0020]      FIG. 13  is a schematic showing of a person using the support extension rails.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]     Referring to  FIG. 1 , which is a side view, a ladder  10  is shown in a vertical or upright erected position. The ladder  10  is an extension ladder and includes an upper ladder section  12 , that is slidably mounted onto a lower ladder section  14 , as is common with present day extension ladders.  
         [0022]     A walk through extension assembly  16  made according to the present invention is shown, and as illustrated in  FIG. 3 , the walk through extension assembly  16  comprises two spaced upright hand rails or supports  18 A and  18 B. The rails  18 A and  18 B ( FIG. 3 ) are mirror images of each other, and each of them includes a base comprising a slip on support tube  20 A and  20 B, respectively, that will slide over ladder side rails  22 A and  22 B ( FIG. 3 ) of the upper section  12  of the ladder. The slip on support tubes  20 A and  20 B are shown as rectangular tubes to fit over the ladder side rails  22 A and  22 B of the ladder  10  shown. The support tube inner walls  24 A and  24 B, as shown typically in  FIG. 4 , are provided with open ended elongated slots  26  (only the slot on wall  24 A is shown), which are of size to slip over the upper two rungs  28 A and  28 B of the upper ladder section  12 . This means that the slip on support tubes can fit snugly over the side rails.  
         [0023]     The slip on support tubes  20 A and  20 B are snugged up or tightened against the ladder rails to fixedly secure the bases or support tubes  20 A and  20 B in place, as will be shown. The securing can be done in any suitable manner that can be selected by the user.  
         [0024]     The upper ends of the slip on support tubes  22 A and  22 B are provided with offset spacer sleeves  30 A and  30 B, respectively, that extend laterally outwardly beyond the ladder side rails  22 A and  22 B. These spacer sleeves  30 A and  30 B in turn support upright extension support hand rails  32 A and  32 B, respectively, which are welded to or otherwise fixed to the spacer sleeves  30 A and  30 B. The upright hand rails define a space indicated by the double arrow  34  between them. The space between the upright hand rails is wider than the space between the ladder side rails, to provide clearance in this space indicated by the arrow  34  for a person or user to pass through. The upright extension hand rails  32 A and  32 B are upright members that are of sufficient height to provide adequate stabilization or support for a person that is moving onto a roof, for example. The user can remain erect and step onto a roof while grasping the hand rails. A sloping roof line is illustrated schematically in dotted lines at  36 , in  FIG. 1 .  
         [0025]     The upright extension hand rails, as shown, are U-shaped tubes, having an upper curved or formed end  38 . The legs of the U-shaped upright extension hand rails are shown at  32 A- 1 ,  32 B- 1 . Legs  32 B- 1  and  32 B- 2  illustrate that the legs of each upright extension hand rails are spaced apart in fore and aft direction sufficiently to permit a person to grip one of the legs of each upright extension hand rail as the user proceeds moving upwardly on the ladder.  
         [0026]     The U-shaped hand rails  32 A and  32 B are made so that a front or outer side legs  32 A- 1  and  32 B- 1  are on the outside of the respective spacer sleeve  30 A or  30 B, and the rear leg, or the leg toward the building, as indicated at  32 B- 2 , is inside of the sleeve  30 A and  30 B, respectively, so that the ends of the rear legs do not jut out from the ladder rail flange  40  that is against the building or the edge of the roof  36 . This means that if the ladder should sink into the ground, the rails  18 A and  18 B would slide along the corner of the roof and would not hook or grab.  
         [0027]     The top ends of the upright extension hand grip rails can be made into a wider loop, if desired, as shown in dotted lines at  42  in  FIG. 1  to provide a larger opening for a hand.  
         [0028]     In order to clamp the bases, comprising slip on support tubes  20 A or  20 B, onto the respective ladder side rail  22 A or  22 B, a suitable releasable clamping mechanism is provided. In the form shown, a thin sheet or strip indicated at  44  (preferably of metal) is hooked at the upper edge of the respective sleeve  20 A or  20 B, as indicated by the hook portion  46  in  FIG. 2 , and is hooked at  48  at the lower end of the sleeve  20 B in  FIG. 2 . The strip  44  is placed on the interior of the slip on support sleeve and can be held in place in other ways, if desired. The ends of such a strip could be riveted to the sleeves or clipped in place.  
         [0029]     A suitable nut or other threaded member  48  is fixed to each of the front walls of the respective sleeve  20 A and  20 B, and a hand wheel that carries a threaded bolt, which is indicated at  50 , can be threaded into the nut  48  and passed through an opening in the sleeve so the end of the bolt bears against the metal strip  44  and forces the strip against the flange of the respective side rail  22 A or  22 B. This will provide a force that will tighten or compress the rear wall of the slip on support tube  20 A or  20 B against the rear flange of the respective ladder side rail. This provides a secure friction lock to hold the upright hand rails  18 A and  18 B in place.  
         [0030]      FIG. 5  shows a perspective view to illustrate the sleeve  30 B, and other components used. The rails are shown as square tubes, but they can be cylindrical tubes as will be shown.  
         [0031]     In  FIG. 6 , a second modified form of the invention is illustrated schematically, and in this case, the ladder is shown at  60 , and it is right at a roof line indicated at  62 . The walk through ladder extension assembly  64  in this form of the invention, comprise two upright hand rails  66 A and  66 B that can be made in a suitable manner. The hand rails have lower inwardly offset support shank sections  68 A and  68 B that fit against outer sides of the side rails  70 A and  70 B of the ladder section  68 A and  68 B. The support shank sections can be held in place with long bolts or shafts  72 A and  72 B that pass through hollow rungs  61  of the ladder  60 . The bolts or shafts are held at the shank section  68 A, and the pass through openings in the shank section  68 B. The shank sections are secured in place, as shown with a pressure bearing threaded hand screw  74  that is mounted on a strap  76  held on bolts or shafts  72 A and  72 B, for example, by washers on the ends of the bolts and threading a nut onto the second ends of both of the bolts.  
         [0032]     The bolts  72 A and  72 B are held in place at shank section  68 A with a strap assembly  78  on the opposite end from the hand wheel  76 . The strap assembly  78  will force the shank section  68 A against the rail  70 A as the threaded hand wheel  74  is tightened to force shank section  68 B against rail  70 B. The tightening action will hold the hand rails  66 A and  66 B in position.  
         [0033]     As can be seen, the spread or lateral distance between the hand rail  66 A and  66 B indicated by the double arrow  80  is also greater than the width of the ladder that is used. The hand rails  66 A and  66 B can be single tubes or straps, or even channel shaped rails.  
         [0034]      FIGS. 7 and 8  illustrate a third form of the invention, wherein a ladder  90  is shown schematically, and it has a series of rungs  92  as well as side rails  94 A and  94 B. A walk through extension hand rail or support assembly indicated at  96  is made to mount on the top two rungs of the ladder, that are illustrated at  92 A and  92 B, specifically. In  FIG. 7 , the extension hand rail support assembly is shown spaced from the ladder  90 . Two walk through hand rails or upright supports are formed to make the extension assembly. A first hand rail or upright  98 A, and a second hand rail or upright  98 B are provided. The hand rails have ladder attachment frames or brackets  100  at lower ends, and as shown, the two hand rails or uprights are joined with cross members  102  and  104  to hold the uprights in the assembly.  
         [0035]     The ladder attachment frames or brackets  100  have upper hooks  106 A and  106 B that will fit over the top rung  92 A. Struts or supports  108 A and  108 B of the attachment frames or brackets  100  have devices  110 A and  110 B at lower ends that are of size to fit over the second rung  92 B, as can be seen in  FIG. 8 . A suitable latch pin  112  is used in each of the devices  110 A and  110 B to hold the hand rail assembly securely in place. When the hooks  106 A and  106 B are placed on the upper most rung  92 A, the devices can be slipped into place on the second rung  92 B. The devices form releasable latches for the brackets  100 .  
         [0036]     The upright extension hand rails or supports  98 A and  98 B, as shown, are offset wider than the ladder rails at their upper portions  114 A and  114 B to provide adequate clearance for a person to walk through or step between the upright extension hand rails onto a roof or other support structure against which the ladder  90  is placed. The upright extension hand rails extend vertically up from the supports  100  and then taper outwardly with inclined sections  98 C and  98 D. The inclined sections  98 C and  98 D join vertical upper portions  114 A and  114 B.  
         [0037]     A fourth form of the invention is shown in exploded view in  FIG. 9 , and in this case, a ladder  119 , and has hollow rungs  116 A and  116 B at least at the top, with the other rungs being shown generally at  116 . The ladder  119  also has side rails  118 A and  118 B that are spaced apart by the hollow rungs  116 A and  116 B, and other rungs  116 .  
         [0038]     The upright extension hand rails or supports in this form of the invention are formed into two separate sections. A first upright hand rail  120 A, and a second upright hand rail  120 B are shown on the opposite sides of the ladder. The walk through upright hand rails  120 A and  120 B have base portions  122 A and  122 B that are generally flat straps that will fit inside any ribs or channel walls on the outside of the ladder side rails  118 A and  118 B. The base portion straps include short tubular nipples  124 A and  124 B that are welded or fixed to the base portion straps  122 A and  122 B. These nipples  124 A and  124 B have bores or apertures shown at  126 A and  126 B, which will receive long bolts  127 , that will pass through the nipples  124 A and  124 B, and through the hollow rungs  116 A and  116 B. The bolts then can be clamped tightly on both sides of the ladder. In the illustration, the bolts  127  are shown in two segments, and they can be made so that they have mating threads at their inner ends and are tightened in the center, or the bolts can pass all the way through the ladder rungs and then have nuts so the straps and the guide rails can be clamped in position on the opposite sides.  
         [0039]     The upright hand rails  120 A and  120 B thus are very sturdy and provide a stable guide for walking through the space between them while grasping the hand rails. It can be seen that the upper portions  121 A and  121 B of the hand rails  120 A and  120 B, are offset with outwardly angled or tapered offset sections  123 A and  123 B to provide an adequate opening for a user to walk through while holding onto the upright hand rails for stabilization.  
         [0040]     It should be noted that the top end of the hand rails or struts will be in the range of  40  inches above the top rung of the ladder to provide for ease of holding and adequate support as an erect person steps through the space between the hand rails or uprights and onto a roof or other support.  
         [0041]      FIG. 10  is a modified version of the first form of the invention, and in this instance, the ladder is again labeled  22 B, and the slip on support sleeve  20 B is illustrated. The clamp screw  50  and nut  48  are also shown. The upper offset sleeve portion  130  is modified and made so that the upright extension hand rails  132 B, including the individual support members  132 B- 1  and  132 B- 2  are slidably placed in sockets  134 A and  134 B that are formed on the sleeve  130 . These sockets will receive the ends of the uprights  132 B- 1  and  132 B- 2 , and the uprights can be fastened or held in place with suitable bolts passing through the walls of the sockets. These bolts are shown at  136 A and  136 B. Securing devices other than bolts can be provided for holding the upright hand rails, or the upright hand rails can merely slip into the sockets if they are stable and secure.  
         [0042]     In this form of the invention, the offset sleeve  130  is provided with receptacles and holders for holding accessories that would be used on a ladder, including tools such as hammers, or paint brushes, paint cans and the like. A tube  140  is illustrated on the interior of the offset bracket  130 , and has an opening of size to receive the handle of a paint brush, for example. Likewise, a tube  142  is on the outside of the sleeve  130 , and can be of size to receive a hammer handle, a wrench, or other tool as well as the handle of a paint brush or paint pad. A paint brush is shown in dotted lines at  143  for illustrative purposes.  
         [0043]     A hook  144  is fixed on one wall of the slip on support sleeve  20 B, and can be used for hanging a paint can, as can the hook  146  which is fixed on the offset sleeve  130 . In this form, the walk through upright extension hand rails  132  can be removed by removing the bolts  136 A and  136 B, and the slip on support tubes or bases  20 A and  20 B can be left in place on the ladder side rails. Then, when the ladder is used for other tasks, such as painting, repair or the like, the holders shown are usable. The accessory holders will be available with or without having the walk through upright hand rails in place.  
         [0044]      FIGS. 11, 12  and  13  illustrate a further modified form of the invention which incorporates the features shown in  FIG. 1 , but shows cylindrical tubing used for forming the upright rails.  
         [0045]     A ladder shown at  150  has side rails  152 A and  153 B with rungs  154  extending between the side rails. A walk through upright extension assembly  156  comprises two spaced apart upright extension hand rails  158 A and  158 B. These hand rails have base sections or supports  160 A and  160 B, which are the slip on tubes that slip over the side rails  152 A and  152 B. The slip on tubes have long slots, one of which is shown at  162  for the side rail  158 A, and slide over the top two rungs  154  of the ladder  150 . Slip on tubes  160 A and  160 B are held in place with threaded hand wheels  164 A and  164 B, which can act directly against the side rails of the ladder, or can act against a lock strip as shown in  FIG. 2 . In any event, the hand wheels  164 A and  164 B are used for holding the bases or slip on supports  160 A and  160 B in place on the ladder side rails.  
         [0046]     The upright U-shaped tubular members  166 A and  166 B are formed so that they will have lower portions  168 A and  168 B that are secured to the slip on tubes  160 A and  160 B. At the front or outer surface of the base sections or supports, the lower sections  168 A and  168 B end above the hand wheels  160 A and  160 B. On the backside or inner side, the lower portions of the legs of the U-shaped extension hand rails are fixed to the top of the slip on tubes, and flush with the rear surface of the slip on tubes so they form smooth continuations of the rear surfaces.  
         [0047]     The uprights  166 A and  166 B include laterally outwardly extending sections  170 A and  170 B that extend laterally out from the slip on supports  160 A and  160 B, and the lower portions  168 A and  168 B, to provide for a wider space between upper portions  172 A and  172 B of the upright extension hand rails. Thus, it can be seen that in this form the upright extension hand rails  158 A and  158 B are smoothly formed, and have rounded upper ends that are easy to grip, and yet the upper portions are spaced apart to permit a person to walk through as shown in  FIG. 13 . The laterally outwardly extending sections do not have to be tapered, but can be horizontal sections joined to the lower portions  168 A and  168 B by a 90° bend to provide the horizontal offset, and the horizontal sections joined to the upper portions by a second 90° bend. The offset portions can be reinforced by doubling the tubes for that section.  
         [0048]     At the lower portions of the front side of the slip on support tubes  160 A and  160 B outwardly and upwardly tapered guides and hand wheel protectors are provided. As shown, there are tapered end sections of tubing  176 A and  176 B. The protector guides can be flat straps that are tapered out from the front surface of the support tubes, and then supported back to the front surfaces. This modified form is shown schematically on bracket  160 B in  FIG. 13  at  177 B. The protector guides  176 A and  176 B have gently tapered lower end sections that will act as guides so that clothing and tools will be guided past the hand wheels  164 A and  164 B as a user moves up to mount the ladder and walks through the rails  158 A and  153 B. Also, the protector guides extend out far enough so if the ladder is dropped, they will protect the hand wheels from damage.  
         [0049]     The tubing that is used for the upright hand rails  166 A and  166 B is easily formed into the gently tapered section  120 A and  120 B configuration to widen out the upper portions  172 A and  172 B sufficiently to permit a user, as shown in  FIG. 13 , to hold onto the upright portions of the railings for stability, and for walking through the supports, while erect, to reduce the awkward movements needed when exiting or moving from the upper end of an upright ladder. The same type of support from the upright hand rails is available when the user is entering the ladder to descend from the roof or other support structure.  
         [0050]     The upright hand rails are elongated a sufficient amount for use by tall or shorter people.  
         [0051]     Another feature of the system shown is that the hand rails can be attached to a ladder and removed without using any special tools.  
         [0052]     Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.