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BACKGROUND OF THE INVENTION  
         [0001]    This invention was invented to produce an easier and safer method of leveling ladders on stairs and inclines as opposed to the old fashioned boards, bricks, and books method and less versitile mechanical systems. It falls certainly under U.S. Patent classification # 182/204 and with its versitile Holding Bracket probably others.  
           [0002]    The Holding Bracket for this ladder leveler unlike other ladder levelers can be non-invasively, hand attached with nuts and bolts to the left inner side, the right inner side, the left outer side and the right outer side of all standard extension ladders.  
           [0003]    The use of a threaded level rod dropped through two proprietary hole locations in the Holding Bracket and fastened in place by an ordinary wing or hex nut reduces the possibility of collapse due to slippage inherent in systems relying on pin and spline and other non nut fasteners.  
           [0004]    The threaded rod and wing/hex nut system also permits the tightest leveling tolerance of any of the other systems observed.  
         SUMMARY OF THE INVENTION  
         [0005]    The Adjusto-Rod Ladder Leveler is an offset device utilizing a Holding Bracket that is uniquely attachable to the left inner side, the left outer side, the right inner side, and the right outer side of all standard extension ladders. This versatile ability to attach to any of the two inner or two outer sides of a standard extension ladder is the result of the inventors, hopefully patentable, Specifications for configuring the location of holes in the Holding Bracket. The Specifications are based on the principle that although standard extension ladder rungs may be quite different in diameter or width they are all set approximately twelve (12) inches apart center point to center point.  
           [0006]    The inventors have incorporated the above principle into a set of proprietary hole location Specifications and produced a prototype. For the left or right inner side attachment, two u-bolts are placed around the bottom two ladder rungs and then through four “specified” holes in the Holding Bracket. For the left or right outer side attachment, two threaded tie rods are placed through two of the above four “specified” holes, each of these two “specified” through holes being located twelve (12) inches from the other, center point to center point. Next two tie-rods are placed through two “Conical Shims”, and then through the bottom two ladder rungs, and lastly through two more “Conical Shims”. The u-bolts and tie-rods are able to securely fasten, the Holding Bracket to the above mentioned four sides of any standard extension ladder by the tightening of ordinary wing and hex nuts affixed to the above mentioned u-bolts and tie-rods.  
           [0007]    The Threaded Adjusto-Rod (Threaded Level Rod) housed by the Holding Bracket is the inventors prefered method for leveling ladders, although other methods, such as a pin and spline systems, could easily be used in conjunction with this unique Holding Bracket.  
           [0008]    When dropped through two additional “specified” holes, there being six in total, including the above four, and when secured in place by a simple wing or hex nut the Threaded Level Rod system reduces the possibility of collapse due to slippage inherant other non nut affixed systems. The inventors Threaded Level Rod and nut system also permits a tighter leveling tolerance than other observed systems.  
       
    
    
     LISTING OF DRAWINGS  
       [0009]    Sheet # 1, FIG. 1 shows the threaded level rod, with the screw on non skid tip and adjustable lower wing and upper hex nut attached.  
         [0010]    Sheet # 2 shows FIG. 2, the primary section of the ladder attachable Holding Bracket with its proprietary hole locations and FIG. 3 the secondary section of the of the attachable Holding Bracket.  
         [0011]    Sheet # 3 FIG. 4 shows the assemblage of FIGS. 1, 2 and  3 .  
         [0012]    Sheet # 4 FIG. 5 shows the two u-bolts that go through the four proprietary hole locations in FIG. 2. for left and right inner side extension ladder attachment.  
         [0013]    Sheet # 5 FIG. 6 shows the inner side attachment of FIGS. 1, 2,  3  and  4  to a standard extension ladder.  
         [0014]    Sheet # 6 FIG. 7 shows the method of left and right outer side extension ladder attachment with two tie-rods, and four conical shims, utilizing two of the proprietary hole locations in FIG. 2 and ordinary wing and hex nuts.  
         [0015]    Sheet # 7 FIG. 8 shows assemblage and attachment of FIGS. 1, 2,  3 ,  4 , and  7  to a standard extension ladder.  
     
    
     DESCRIPTION OF THE INVENTION  
       [0016]    The Universal, Left Or Right, Inner Or Outer Side, Hand Attachable Threaded Adjusto-rod leveler is an offset device designed to bring all standard extension ladders to a level position when resting on stairs or inclines.  
         [0017]    The above is accomplised by adjusting a threaded level rod downward through two centered holes drilled through the upper and lower horizontal sides of a three sided Holding Bracket attached to the non elevated (downhill) side of the ladder until the extended threaded level rod raises the leg on the (downhil) side of the ladder to the level of the leg on the (uphill) side of theladder. When the ladder is in this level upright position the threaded level rod is set in place by a wing nut tightened upward against the lower part of the Holding Bracket and a hex nut tightened downward against the upper part of the Holding Bracket.  
         [0018]    A rubberized screw-on non skid tip attaches to the bottom of the threaded level rod.  
         [0019]    The inventors prototype is made of steel, mostly stainless. It could, however, except for the current cost, be made from space age plastic.  
         [0020]    The device has three basic components or sections which can be assembled with “off the shelf” 0  nuts and bolts.  
         [0021]    The first section consists of a threaded steel level rod, cut to the inventors specification, an, off the self, screw-on non skid tip, an off the shelf wing nut, and an off the self hex nut. (see FIG. 1)  
         [0022]    The attachable Holding Bracket for the threaded level rod has two section.  
         [0023]    The primary section of the Holding Bracket is fabricated from a bar of stainless steel that is cut, drilled, and bent to the inventors specifications. (see FIG. 2)  
         [0024]    The ability to attach to any of the two inner or two outer sides of any standard extension ladder is the result of the hopefully patentable, specifications for configuring the location of the holes in the primary section of the Holding Bracket. These Proprietary specifications are base on the principle that although standard extension rungs may be quite different in diameter or width they are all set approximately twelve (12) inches apart center point to center point.  
         [0025]    The secondary section of the Holding Bracket is also fabricated from a bar of stainless steel that is cut, drilled, and bent to the inventors specifications. (see FIG. 3)  
         [0026]    The “REFERENCE NUMBERS (RN)”: for FIGS. 1, 2, and  3  detail both the patentable and preferred specifications for the three basic components or sections of the Hand Attachable Threaded Adjusto-rod Ladder Leveler.  
         [0027]    [0027]FIG. 4 with its detailed “RN” shows the three basic sections assembled but unattached to a ladder and without any fasteners.  
         [0028]    [0028]FIG. 5 with detailed “RN” shows the primary section of the Holding Bracket with its two off the shelf u-bolt, wing nut, hex nut fasteners for inside attachment.  
         [0029]    [0029]FIG. 6 shows an assembled Threaded Adjusto-rod Ladder Leveler attached to the inside of a standard extension ladder. Two off the shelf u-bolts #  14  and  17  are places around the bottom two sequential standard ladder rungs. The ends are then pushed through the proprietary holes in the primary section of the Holding Bracket (RN) #  9 ,  10   11 , and  12 . Finally they are hand affixed firmly to (RN) #  6  using (RN) #  15 ,  16 ,  18 ,  19 .  
         [0030]    [0030]FIG. 7 with its detailed (RN) shows the primary section of the Holding Bracket with fasteners consisting of two off the shelf threaded tie-rods, two wing nuts, two hex nuts, and four proprietary conical shims used for outside attachment.  
         [0031]    [0031]FIG. 8 shows an assembled Threaded Adjusto-rod Ladder Leveler attached to the outside of a standard extension ladder. Tie-rods (RN) #  33  and  34  are inserted through the bottom two sequential standard ladder rungs. Next a proprietary conical shim (RN) #  37  is placed narrow end first around the four protruding tie-rod ends and pushed tightly into the four sequential ladder rung ends. Threaded rod (RN) #  33  is next inserted through hole (RN) #  9  in the primary section of the Holding Bracket (RN) #  5  and threaded rod (RN) #  34  is inserted through hole (RN) #  11  in the primary section of the Holding Bracket. (note: holes (RN) #  9  and  11  are twelve inches apart center-point to center-point as are all standard sequential ladder rungs).  
         [0032]    Finally the two hex nuts (RN) #  35  are screwed onto the two tie-rod ends of (RN) #  33  and  34  at the junctures of holes (RN) #  9  and  11  in the primary section of the Holding Bracket and two wing nuts (RN) #  36  are screwed onto the opposite ends of tie-rods (RN) #  33  and  34  and firmly hand tightend against the two proprietary conical shims at that end of tie-rods (RN) #  33  and  34 .  
       REFERENCE NUMBERS  
       [0033]    [0033] 1 =A threaded level rod that drops through holes #  13  and #  24   
         [0034]    [0034] 2 =The wing nut at the lower end of the threaded level rod  
         [0035]    [0035] 3 =The hex nut at the upper end of the threaded level rod  
         [0036]    [0036] 4 =The screw on non skid tip on the lower end of the threaded level rod  
         [0037]    [0037] 5 =The primary section of the ladder attachable Holding Bracket  
         [0038]    [0038] 6 =The vertical side of the primary section of the ladder attachable holding bracket  
         [0039]    [0039] 7 =The 90% angle at the lower end of the primary section of the ladder attachable Holding Bracket  
         [0040]    [0040] 8 =The horizontal side of the primary section of the ladder atachable Holding Bracket which forms a 90% angle with the verticle side of the Holding Bracket  
         [0041]    [0041] 9 =The top attachment hole in the primary section of the ladder attachable Holding Bracket  
         [0042]    [0042] 10 =The hole located next below #  9   
         [0043]    [0043] 11 =The hole located in the lower Quadrant of the primary section of the ladder attachable Holding Bracket  12  inches distance from #  9  center point to center point  
         [0044]    [0044] 12 =The hole in the lower Quadrant of the primary section of the ladder attachable Holding Bracket below #  11  and  12  inches distance from #  10  center point to center point  
         [0045]    [0045] 13 =The hole in #  8  which is aligned with #  24  through which drops #  1   
         [0046]    [0046] 14 =the u-bolt, the ends of which, go through holes #  9  and #  10  for left or right inside attachment  
         [0047]    [0047] 15 =The wing nut that fastens to the u-bolt at hole #  9   
         [0048]    [0048] 16 =The hex nut that fastens to the u-bolt at hole #  10   
         [0049]    [0049] 17 =The u-bolt, the ends of which, go through holes #  11  and #  12  for inside attachment  
         [0050]    [0050] 18 =The hex nut that fastens to the u-bolt at hole #  11   
         [0051]    [0051] 19 =The wing nut that fastens to the u-bolt at hole #  12   
         [0052]    [0052] 20 =The secondary section of the attachable Holding Bracket that bolts on to #  6  through two holes the lower one a wing nuts&#39; clearance distance, above hole #  11   
         [0053]    [0053] 21 =The vertical side of #  20  that bolts onto #  6   
         [0054]    [0054] 22 =The 90% angle at the lower end of #  20   
         [0055]    [0055] 23 =The horizontal side of #  20   
         [0056]    [0056] 24 =The hole in #  23  which is aligned with hole #  13  through which drops #  1   
         [0057]    [0057] 25 =The lower locking hole through #  21 , that is aligned with hole #  26   
         [0058]    [0058] 26 =The locking hole in #  6  that is aligned with hole #  25   
         [0059]    [0059] 27 =The upper locking hole through #  21 , that is aligned with hole #  28   
         [0060]    [0060] 28 =The upper locking hole through #  6 , that is aligned with hole #  27   
         [0061]    [0061] 29 =The lower locking bolt that goes through locking holes #  25  and #  26   
         [0062]    [0062] 30 =The upper locking bolt that goes through locking holes #  27  and #  28   
         [0063]    [0063] 31 =The locking nut that fastens bolt #  29   
         [0064]    [0064] 32 =The locking nut that fastens bolt #  30   
         [0065]    [0065] 33 =The tie-rod for left or right side outer attachment that goes through hole #  9  then through a conical shim #  37  then through the next to bottom rung of any standard extension ladder and finally through a second conical shim #  37  located at the far end of the above next to bottom rung  
         [0066]    [0066] 34 =The tie-rod for left or right outer side attachment that goes through hole #  11  then through a conical shim #  37  then through the bottom rung of any standard extension and finally through conical shim #  37  located at the far end of the above bottom rung  
         [0067]    [0067] 35 =Either of the hex nuts that fasten the two ends of the two tie-rods through holes #  9  and #  11   
         [0068]    [0068] 36 =Either of the wing nuts that fasten the two ends of the two tie-rods to the two conical shims inserted into the two far openings of the bottom two rungs of any standard extension ladder.  
         [0069]    [0069] 37 =Any of the conical shims through the tie-rods are passed and that are inserted into the the openings at the two ends of the bottom two rungs of any standard extension ladder

Summary:
A ladder leveling device, the Holding Bracket of which, is hand attachable to the left inner side, the right inner side, the left outer side and the right outer side of all standard extension ladders utilizing proprietary hole location specs., standard nuts and bolts and proprietary conical shims. Leveling is accomplished by dropping a threaded level rod through specified holes in the Holding Bracket and securing in place with an ordinary wing or hex nut.