Patent Abstract:
A device for stabilizing a ladder has a clamp adapted to engage a side rail of the ladder, an arm extending from the clamp and a screw member disposed at the end of the arm. The ladder is leaned against the roof in the conventional manner and the device is positioned on the side rail of the ladder with the arm extending under the eaves. The screw member is then tightened against the underside of the roof (or against the soffit if there is one) to secure the ladder in position.

Full Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates to a device for stabilizing a ladder used to provide access to the roof of a structure. More specifically, the invention relates to a device that engages the eaves of a roof and secures the ladder in position.  
         [0003]     2. Background  
         [0004]     Ascending a ladder to the roof of a structure is inherently dangerous. Typically, the ladder is leaned against the edge of a roof, which may not provide adequate stability. If not secured in some fashion, the ladder may fall to one side or may fall backward away from the roof. A number of inventions have been proposed to address this problem. Quite a few patents have been issued for devices intended to stabilize a ladder. These include, for example:  
                                                       Patent Number   Inventor(s)   Issue Date                           783,259   Friend   Feb. 21, 1905           1,467,597   Wendel   Sep. 11, 1923           2,815,160   Gilmour et al.   Dec. 3, 1957           4,823,912   Gould et al.   Apr. 25, 1989           4,949,810   Dwinnell   Aug. 21, 1990           5,012,895   Santos   May 7, 1991           5,067,588   Bendickson   Nov. 26, 1991           5,117,941   Gruber   Jun. 2, 1992           5,165,501   Donahey   Nov. 24, 1992           5,180,032   Hidalgo   Jan. 19, 1993           5,383,533   Nikula et al.   Jan. 24, 1995           5,509,500   Delagera   Apr. 23, 1996           5,743,356   Mitchell   Apr. 28, 1998           5,775,465   Vossler   Jul. 7, 1998           5,971,100   DeLeon et al.   Oct. 26, 1999           6,009,974   Jones   Jan. 4, 2000           6,012,546   Bee et al.   Jan. 11, 2000           6,019,191   Flores   Feb. 1, 2000           6,045,102   Terenzoni   Apr. 4, 2000           6,394,229   Hastreiter   May 28, 2002           6,412,600   Wolfman   Jul. 2, 2002           6,427,803   Moore   Aug. 6, 2002           6,513,625   Gaskins   Feb. 4, 2003           6,578,665   DeBaca et al.   Jun. 17, 2003                      
 
       SUMMARY OF THE INVENTION  
       [0005]     The present invention is directed to a device for stabilizing a ladder. In one embodiment the device comprises a clamp adapted to engage a side rail of the ladder, an arm extending from the clamp and a screw member disposed at the end of the arm. The ladder is leaned against the roof in the conventional manner and the device is positioned on the side rail of the ladder with the arm extending under the eaves. The screw member is then tightened against the underside of the roof (or against the soffit if there is one) to secure the ladder in position.  
         [0006]     In another embodiment, a ladder stabilizer is configured as a strap that may be wrapped around the side rails of a ladder and nailed to a roof. The strap has fittings at each end that facilitate coupling two or more straps together end to end.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]      FIG. 1  is a perspective view showing a ladder stabilizer in accordance with the present invention.  
         [0008]      FIG. 2  is a diagrammatic view showing the device in use to stabilize a ladder against a roof.  
         [0009]      FIG. 3  illustrates a strap device for stabilizing a ladder.  
         [0010]      FIG. 4  is a perspective view of an end fitting for the strap shown in  FIG. 3 .  
         [0011]      FIG. 5  is a plan view of the end fitting shown in  FIG. 4 .  
         [0012]      FIG. 6  is a partial cross-sectional view through line  6 - 6  of  FIG. 5 .  
         [0013]      FIG. 7  illustrates another strap device for stabilizing a ladder.  
         [0014]      FIG. 8  is a detailed view of the strap assembly shown in  FIG. 7 .  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]     In the following description, for purposes of explanation and not limitation, specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods and devices are omitted so as to not obscure the description of the present invention with unnecessary detail.  
         [0016]      FIG. 1  shows a ladder stabilizer  10  in accordance with the present invention. The stabilizer comprises a clamp portion  20 , an arm  30  extending from the clamp portion and a screw  40 . Clamp portion  20  includes a pair of grips  21  that are slotted to engage rail  102  of ladder  100 .  
         [0017]     The length of arm  30  is preferably adjustable. To facilitate this, arm  30  comprises an outer section  31  and an inner telescoping section  32 . A pin  34  engages one of a plurality of holes  35  to secure the telescoping sections together at a desired length. An upward reaching section  33  extends from the end of inner section  32 . Screw  40  is threaded through section  33 . Screw  40  has a handle portion  41  at its lower end and a foot potion  42  at its upper end.  
         [0018]     Various materials are suitable for the construction of ladder stabilizer  10 . The principal components could be constructed of steel or aluminum or a combination of the two materials. For reasons of economy and versatility, plastic is a preferred material.  
         [0019]     With reference now to  FIG. 2 , the use of ladder stabilizer  10  may be better understood. Rails  102  of a ladder  100  are leaned against the edge of roof  110 . As mentioned above, the grips  21  of clamp  20  are adapted to engage rail  102 . The angle between arm  30  and clamp  20  may be adjusted by means of adjustment knob  22  to accommodate different roof overhangs, gutters and fascia dimensions. Once the angle of arm  30  has been adjusted, screw  40  is tightened by means of handle  41  until the foot  42  engages the underside of the roof. It will be appreciated that tightening the screw  40  exerts a downward force on arm  30 , which, in turn, applies a clockwise force on clamp  20  to more tightly engage ladder rail  102 . This also forces the ladder against the edge of the roof to firmly secure it in place. Preferably, a stabilizer is used on each of the ladder rails for maximum stabilizing effect.  
         [0020]     It should be noted that stabilizer  10  may also be used with a “parapet” style roof. In this case, the stabilizer is simply inverted and the screw member is tightened against the top of the parapet.  
         [0021]      FIGS. 3-6  show a strap  200  for stabilizing ladder  100  against the edge of roof  110 . The strap may be simply wrapped around the side rails  102  of the ladder and nailed to the roof at each end.  
         [0022]     The construction of strap  200  can be better seen in  FIGS. 4 and 5 . The strap comprises a length of flexible material  202 , such as nylon webbing. An end fitting  204  is secured at each end of the strap. Material  202  is looped through a slot  205  in the end fitting and sewn together. Nail holes  206  are provided for securing the ends of the strap to a roof.  
         [0023]     A feature of strap  200  is the provision of means for coupling together two or more of the straps end to end. End fittings  204  have a pair of locking prongs  207  and a pair of locking prong holes  208 . The holes are configured to receive the locking prongs of another end fitting that has been inverted and aligned with the first fitting. The locking prong holes  208  of each end fitting receive the locking prongs  207  of the other end fitting. The locking prongs are shaped so that, once the two end fittings have been placed together, the locking prongs extend over the surface of the adjacent end fitting to secure them together.  
         [0024]     Each of end fittings  204  is provided with a safety clip  210  to prevent unintended uncoupling of coupled end fittings. Safety clip  210  is separated from end fitting  204  on three sides so that it can deflect slightly from the plane of the fitting. The safely clip has a saw-tooth cross-section as illustrated in  FIG. 6 . When a pair of end fittings are coupled together, the opposing safety clips engage each other as the locking prongs are slid over the respective locking prong holes. This prevents the unintentional uncoupling of the end fittings since the safety clips must be manually separated before the locking prongs can be removed from their respective locking prong holes.  
         [0025]      FIGS. 7 and 8  show another type of strap assembly  300  for stabilizing ladder  100  against the edge of roof  110 . As shown, a pair of strap assemblies  300  are used, one with each of the side rails  102  of the ladder. The assembly comprises a first strap portion  302  secured at one end to end fitting  304  and at the other end to adjustment clamp  305 . A second strap portion  303  is releasably secured by the adjustment clamp. Strap portions  302  and  303  may be made of nylon webbing as in the previously described embodiment.  
         [0026]     Each of the strap assemblies is secured to the roof at end fitting  304  by nails driven through slotted holes  306 . Strap portion  303  is wrapped around the respective side rail of ladder  100  and threaded through loop  307  like a slipknot in a lasso. The free end of strap portion  303  is then threaded through adjustment clamp  305  and secured taught.  
         [0027]     End fitting  304  is formed with bends so that portion  308 , which connects to strap portion  302 , is raised off of the surface of the roof. The bends also provide an upright surface  310 , which may be struck with a hammer to dislodge the end fitting from the securing nails. End fitting  304  is preferably made of metal strap material, such as steel, which is plated or otherwise treated for corrosion protection.  
         [0028]     When ladder  100  is to be relocated, tension in the strap assemblies is released at the adjustment clamps, and the end fittings are tapped off of the nails and removed.  
         [0029]     It will be recognized that the above-described invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the disclosure. Thus, it is understood that the invention is not to be limited by the foregoing illustrative details, but rather is to be defined by the appended claims.

Technology Classification (CPC): 4