Patent Publication Number: US-7905458-B2

Title: Ladder accessory device

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/132,202, filed Jun. 17, 2008 entitled “Ladder Hand.” 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to ladder accessory devices, and more particularly to a device for attaching to a ladder to hold materials, tools, equipment, supplies or other items. 
     BACKGROUND OF THE INVENTION 
     Portable ladders, such as fixed ladders, extension ladders and step ladders, may be used by handymen, technicians and other persons for performing tasks. In some cases a step ladder may include a shelf for supplies. Typically, fixed ladders and extension ladders do not include a shelf. Accordingly there is a need for ladder accessory products. In particular it is desirable to have an accessory product for holding materials and tools, such as paint cans and paint brushes. 
     An example conventional ladder accessory typically hangs or clips on a ladder rung and hangs towards the center of the ladder creating an awkward maneuver to reach the paint can or tools. Some are simple platforms which hook to two rungs with no positive fasteners to keep the paint can on the platforms. Other ladder accessories insert into a hollow rung of a ladder and are self leveling but typically cannot be used with accessories such as paint and tool trays. 
     Accordingly, there is a need for an easy to use ladder accessory, such as may be used for safely supporting supplies, materials, tools and equipment. These and other needs are addressed by the inventions described herein. 
     SUMMARY OF THE INVENTION 
     The present invention provides a ladder accessory device for supporting, materials, supplies, equipment or tools. The device may be secured to a hollow-rung ladder with a sleeve of an arm engaging the hollow rung. The arm is generally free to rotate about a first axis defined by the length of the sleeve. A member engages the arm at a first joint about which the arm/sleeve may move. A platform engages the member at a second joint about which the platform may move. Motion about the first axis and motion about the first joint are generally free to enable the platform to be generally self-leveling in two directions while the member suspends the platform at a level lower than the arm. In some embodiments range of motion of the first joint and second joint extend sufficiently to allow the arm, member and platform to be stored in a generally parallel alignment. 
     The invention will be better understood by reference to the following detailed description taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is further described in the detailed description that follows, by reference to the noted drawings by way of non-limiting illustrative embodiments of the invention, in which like reference numerals represent similar parts throughout the drawings. As should be understood, however, the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings: 
         FIG. 1  is an illustration of a ladder accessory device, according to an example embodiment of the present invention; 
         FIG. 2  is an exploded view of the ladder accessory device of  FIG. 1 ; 
         FIG. 3  is a diagram of an arm of the ladder accessory device installed within a hollow rung of a ladder; 
         FIG. 4  is an illustration of a joint between an arm and a connecting member of the ladder accessory device, according to an example embodiment of the present invention; 
         FIG. 5  is an illustration of a joint between a platform and the connecting member of the ladder accessory device, according to an example embodiment of the present invention; 
         FIG. 6  is a partial illustration of the connecting member at an end forming a portion of the joint with the platform, according to an example embodiment of the present invention; 
         FIG. 7  is a partial illustration of the platform at an end forming a portion of the joint with the connecting member, according to an example embodiment of the present invention. 
         FIG. 8  is an illustration of the ladder accessory device of  FIG. 1  in a closed position; and 
         FIG. 9  is another illustration of the ladder accessory device of  FIG. 1  in a closed position. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     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. 
     According to an embodiment of the present invention, a ladder accessory device is self-leveling to support materials, supplies, equipment or tools. When the ladder is moved while the accessory device is installed, a platform portion of the accessory device remains generally level. In particular, movement is generally free about two axes, which enables the ladder accessory device to move and the platform to remain generally level.  FIGS. 1-2  show an example embodiment of a ladder accessory device  100  including three members  102 ,  104 ,  106 . One member is an arm  106  which may engage a hollow rung of a ladder. Another member is a platform  102  which may support the materials, supplies, equipment or tools. For example, the platform  102  may support a paint can or other container. The third member is a connecting member  104  between the arm  106  and the platform  102 . The arm  106  may move relative to the connecting member  104  at one joint  110 . The platform  102  may move relative to the connecting member  104  at a second joint  112 . 
     In some embodiments the arm  106  is made of a hard, generally rigid, plastic material. A sleeve  108  may concentrically surround a substantial length of the arm. In an example embodiment the sleeve  108  may be formed by a hard plastic material at an inner surface adjacent to the arm and a soft rubber or other pliable material at an external surface outward from the arm  106 . Relative movement between the sleeve  108  and arm  106  is free about an axis defined by the length of the arm (and coaxially located sleeve). In particular the sleeve is free to rotate while remaining on the arm with the hard plastic inner surface of the sleeve moving relative to the hard plastic outer surface of the arm. A cap may be attached (e.g., snapped into place) or otherwise positioned at the end of the arm and sleeve to keep the arm from sliding out from the sleeve. Thus, movement between the sleeve  108  and arm  106  is generally restricted along the length of the arm, so as to keep the arm from separating from the sleeve during normal use. 
     As shown in  FIG. 3 , one manner of installing the accessory device  100  is to slide the arm and surrounding sleeve into an opening  114  of a ladder&#39;s  116  hollow rung  118 . For some ladders, there is a lip at the opening to the hollow rung. The diameter of the sleeve  108  is generally less than the diameter or other cross sectional dimension of the rung&#39;s opening  114 . By having a smaller diameter the ladder accessory device  100  is easy to install and easy to uninstall. The ladder accessory device  100  generally stays inserted within the rung due to the friction between the pliable outer surface of the sleeve  108  and aluminum, metal, fiberglass, or other material forming the walls  120  (and lip) of the ladder&#39;s hollow rung  118 . In particular, the weight of materials being supported by the platform  102  forces a proximal end  124  of the arm closest to the rung opening  114  in a downward direction, while forcing the distal end  126  of the arm in an upward direction. The friction between sleeve  108  and the rung&#39;s inner walls  120  is defined by the coefficients of friction of the outer surface of the sleeve  108  and the inner surface  120  of the ladder&#39;s rung at the points of contact, along with the weight of the accessory device  100  and any materials being supported by the accessory device  100 . Further, the soft outer surface of the sleeve indents at the lip (under the weight of the device  100  and supported materials) to provide additional friction along the various surfaces of the lip contacted by the sleeve. 
     Although the arm  106  remains inserted, the arm  106  may rotate within the hollow rung  118 . More specifically, the arm  106  is free to rotate within the sleeve  108 , while the sleeve  108  is generally fixed and stationary within the hollow rung  118 . Accordingly, as the ladder  116  is moved the weight of the accessory device  100  may rotate the arm  106  (and the rest of the accessory device  100 ) within the sleeve  108 . When materials are being supported by the installed accessory device  100 , the weight of the accessory device  100  in combination with the weight of the materials being supported may rotate the arm  106 . Accordingly, the arm  106  is generally free to rotate about an axis  128  defined by the coaxial lengths of the arm and sleeve to provide a self leveling capability to the accessory device  100  about the axis  128  of rotation. Such axis  128  of rotation is generally parallel with an axis  129  defined by the length of the ladder rung, but may differ slightly due to the arm/sleeve combination having a smaller diameter than the hollow rung  118 . 
       FIG. 4  shows the arm  106  and connecting member  104  coupled together forming the joint  110 . The joint  110  allows relative motion between the arm  106  and connecting member  104  with one degree of freedom (e.g., rotation about an axis  131 ). The joint  110  range of motion may extend from approximately 0 degrees to at least 270 degrees. In some embodiments the range of motion may extend to approximately 360 degrees. 
     In an example embodiment, the joint  110  is formed by an axle  132  at the connecting member  104  and a seat  134  at the arm  106 , (see  FIGS. 2 and 4 ). One of ordinary skill will appreciate that there are many other structures that may be embodied to achieve a joint allowing the arm  106  to move with at least one degree of freedom relative to the connecting member  104 . In the illustrated embodiment, the seat  134  is generally contoured to mate with the shape of the axle  132 . In particular the seat  134  has a generally circular surface which extends less than 360 degrees. An opening between extreme edges of the seat  134  has generally the same, yet a slightly shorter separation than the diameter of the axle  132 . The difference is big enough to keep the seat  134  in place to ride the axle  132  while assembled, yet not so small as to allow the seat  134  to separate from the axle  132  and disassemble the joint  110  without applying a significant force perpendicular to the axle  132  along the line of separation. Accordingly, the arm  106  may snap to the connecting member  104  to mate the seat  134  to the axle  132 . Similarly, the arm may be snapped away from the connecting member to un-mate the seat  134  and axle  132 . 
     As shown in  FIGS. 1 ,  2 , and  4 - 6 , the arm  106  may also include a hook  140 . In an example embodiment the hook  140  is located at the proximal end  124  of the arm  106 . When the accessory device  100  is assembled and installed, the hook  140  may be located to one side of the joint  110  axle  132  (see  FIG. 1 ), while the arm  106  extends within the ladder rung to an opposite side. One of ordinary skill will appreciate that the relative position of the hook  140  may vary. It is desirable that the hook  140  be oriented relative to the connecting member  104  to receive a handle of a paint can or other container that may be supported by the platform  102 . 
     Referring again to  FIG. 2 , the connecting member  104  may extend from a first end  144  positioned near the arm  106  to a second end  146  positioned near the platform  102 . The axle  132  may be located near the first end  144 . An opening  147  may be defined by the connecting member  104  near the axle  132  through which the proximal end  124  of the arm  106 , including the hook  140 , may move during relative motion between the arm  106  and connecting member  104  (see  FIG. 4 ). In some embodiments the arm  106  may include a stop  149  (see  FIG. 2 ), bumper or other surface to define a limit to the range of motion of the joint  110 . For example, the stop  149  may prevent further rotation of the arm  106  at approximately 270 degrees or more by coming up against a surface of the connecting member  104 . Such connecting member surface may be adjacent to the opening  147 . 
     In an example embodiment the connecting member  104  is formed by molded plastic, a resin material or another light weight, generally rigid material. The shape and length of the connecting member  104  may vary. In the illustrated embodiment a ribbed structure is used to define a generally rigid structure. The length of the connecting member  104  may differ for various embodiments. In an example embodiment the connecting member  104  has a length between joints  110  and  112  greater than the height of a target material to be supported, (e.g., greater than the height of a typical one gallon can of paint; greater than the height of a five gallon container). Thus, the hook  140  may be at a level above the container, and the container handle may be supported by the hook  140  at a height greater than the container height. 
     As shown in  FIGS. 1 and 2  the platform  102  extends from the connecting member  104  distally to define a surface for receiving materials, supplies, equipment or tools. In various embodiments the size and shape of the platform  102  may vary according to the materials to be supported. Further, an edge  152 , rim or other structure extending to a height greater than the support surface may be defined to prevent a material resting on the support surface from sliding off the platform  102 . 
     In an example embodiment the platform  102  is formed by molded plastic, a resin material or another light weight, generally rigid material. The shape and length of the platform  102  may vary. In the illustrated embodiment a ribbed structure is used to define a generally rigid structure. Each rib may extend to a common height, in which the distal edge of each rib defines a portion of the support surface. The length of the platform  102  may vary according to the embodiment and the desired material, equipment supplies or tools to be supported by the support surface. 
     In some embodiments, one or more hooks  154  may be attached or integrally formed at the platform  102  to support hanging objects. In particular a tool having an opening, a small container having a handle, or another object may be hung from a hook  154 . In the illustrated embodiment, hooks  154  are located toward a distal end  156  of the platform  102  (see  FIG. 2 ). In other embodiments the hooks  154  may be located anywhere along the periphery of the platform, so as to allow objects to be suspended. 
       FIGS. 1 ,  2  and  5  show the platform  102  and connecting member  104  coupled together forming the joint  112 . The joint  112  allows relative motion between the platform  102  and connecting member  104  with one degree of freedom (e.g., rotation about an axis  171 ). The joint  112  range of motion may extend from approximately 0 degrees to approximately 90 degrees. In alternative embodiments the range of motion may differ. Although the relative position of the joint  112  components at the platform  102  and connecting member  104  may vary, in an example embodiment the joint  112  occurs between one end  146  of the connecting member  104  and a proximal end  158  of the platform  102 . 
     As shown in  FIGS. 6 and 7 , in an example embodiment, the joint  112  may be formed by one or more axles  162  at the connecting member  104  and one or more corresponding seats  164  at the platform  102 . One of ordinary skill will appreciate that there are many other structures that may be embodied to achieve a joint allowing the platform  102  to move with at least one degree of freedom relative to the connecting member  104 . In an example embodiment, each seat  164  may be generally contoured to mate with the shape of the corresponding axle  162 . In particular each seat  164  may have a generally horseshoe shape, including a curved portion surface which receives its corresponding axle  162 . A distance between legs of the horseshoe-shaped inner surface of each seat  164  may be generally the same as the diameter of the axles  162 , or slightly larger, to allow rotation of the axles  162  along the curved portion of the seats  164 . In some embodiments a ridge  166  may be formed along a leg of the inner surface of each seat  164 . Such ridges  166  extend respectively to a height creating a distance from the distal point of the ridge to the opposite leg of the seat  164  which is slightly shorter than the diameter of each axle  162 . The distance is short enough to keep the axle  162  in place to ride the seat  164  while assembled, yet not large enough to allow the axle  162  to separate from the seat  164  and disassemble the joint  112  under normal operating conditions. To assemble the joint  112 , the connecting member  104  axles  162  are inserted into the horseshoe-shaped seats  164  and forced past the respective ridges  166  to rest in the curve of the respective seats  164 . Accordingly, the platform  102  may snap to the connecting member  104  to mate each seat  164  to its corresponding axle  162 . Similarly, the platform  102  may be snapped away from the connecting member to un-mate the seats  164  and axles  162 . 
     Respective openings  187  (see  FIGS. 5 and 6 ) may be defined by the connecting member  104  near the axles  162  through which the seats  164  of the platform  102  may move during relative motion between the platform  102  and connecting member  104 . Referring again to  FIGS. 6 and 7 , one end of the range of motion for joint  112  is limited by the surfaces  182  located between each of the respective seats  164  and the surfaces  184  between each of the respective axles  162 . At the end of the range of motion shown in  FIG. 5  (e.g., at an approximately 90 degree angle between the platform  102  and connecting member  104 ) the surfaces  182 ,  184  butt up against each other. 
     In an example embodiment both the connecting member  104  and platform  102  are generally ribbed structures. Such ribs are offset so as to allow the ribs of the platform  102  to mate with recessions between ribs of the connecting member  104 . Similarly the ribs of the connecting member  104  may mate with recessions between ribs of the platform  102 .  FIGS. 8 and 9  show the ladder accessory device  100  in a storage position in which the ribs of the platform and connecting member are mated. At such mated position, the joint  112  is at one extreme of its range of motion—a beginning position where the platform  102  and connecting member  104  form an angle of approximately zero degrees. While in the storage position, the joint  110  also is at one extreme of its range of motion—a beginning position where the arm  106  and connecting member  104  form an angle of approximately zero degrees. Within such storage position, the arm  106 , connecting member  104  and platform  102  are aligned to extend generally parallel to each other. 
     To alter the orientation of the accessory device  100 , the arm  106  may be rotated about the axis  131  at joint  110 . When the arm  106  is rotated to approximately 90 degrees relative to the connecting member  104 , the platform  102  may be rotated about the axis  171  at joint  112 . Note that the platform  102  may be free to start motion about axis  171  before the arm  106  completely clears the path of the platform  102 . Furthermore, in embodiments where the axle  132  is offset from the distal end of the platform  102  while the accessory device  100  is in the storage position, the arm  106  clears the path of the platform  102  before the arm  106  is rotated to 90 degrees relative to the connecting member  104 . 
       FIG. 1  shows the ladder accessory device  100  with the arm  106  oriented at approximately 270 degrees relative to the connecting member  104 , and the platform  102  oriented at approximately 90 degrees relative to the connecting member  104 . In an example embodiment these positions are the end positions for the range of motion of the joints  110 ,  112 . To install the ladder accessory device  100 , the arm  106 /sleeve  108  is inserted into the hollow rung of a ladder. As the ladder is angled relative to a wall against which the ladder leans, the ladder accessory device  100  self levels as the arm  106  rotates within the sleeve  108 , while the sleeve  108  remains generally stationary within the hollow rung. When a worker moves the ladder with the accessory device  100  installed, the angle of the ladder relative to the wall surface may change. In addition the ladder may be tipped slightly so that one leg of the ladder is higher from the ground relative to the other leg. The ladder accessory device  100  is self leveling relative to the angle between the ladder and the wall based upon rotation of the arm within the sleeve. The ladder accessory device  100  is self leveling relative to the tilt of the ladder relative to the earth surface (i.e., one ladder leg at different height than other ladder leg) by relative movement between the arm  106  and connecting member  104  at joint  110  axis  131 . For example as the ladder is tilted for the leg having the accessory device to be lower than the other leg, the angle between the arm  106  and support member may adjust to be less than 270 degrees. As ladder is tilted for the leg having the accessory device to be higher than the other leg, the angle between the arm  106  and support member may adjust to be greater than 270 degrees (where the range of motion for such embodiment exceeds 270 degrees). 
     The ladder accessory device  100  has several benefits and advantages. In particular, the device  100  is self-leveling along two axes. It can be attached to a ladder with one hand. It may be pre-assembled for shipping to stores, and thus requires no assembly by the user. The device  100  can be flipped open from the closed position shown in  FIGS. 8 and 9  to the open position of  FIG. 1  with one hand and be ready for use. The device  100  folds flat for easy storage. The device  100  may position a paint can or other container to the side of ladder for safer and more comfortable use. The device hooks  154  may hold paint brushes while moving the ladder. Non-slip material on the sleeve  108  reduces chances of device  100  sliding off the ladder. Further, the ladder even may be moved while a paint can stays attached to the installed device  100 . In some embodiments the accessory device can safely hold containers weighing up to 20 pounds. In different embodiments lighter or heavier weights may define the safe limits. 
     It is to be understood that the foregoing illustrative embodiments have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the invention. Words used herein are words of description and illustration, rather than words of limitation. In addition, the advantages and objectives described herein may not be realized by each and every embodiment practicing the present invention. Further, although the invention has been described herein with reference to particular structure, materials and/or embodiments, the invention is not intended to be limited to the particulars disclosed herein. Rather, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims. Those skilled in the art, having the benefit of the teachings of this specification, may affect numerous modifications thereto and changes may be made without departing from the scope and spirit of the invention.