Patent Abstract:
A transport assembly for transporting an object axially along a rail of a ladder. The assembly comprises a platform for supporting the object at a selected axial position. A coupling mechanism is employed to slidably connect the platform to the rail. The coupling mechanism includes a locking mechanism and a connector for connecting the coupling mechanism to the platform. Axial displacement of the object along the rail is such that the locking mechanism permits relative axial displacement of the assembly with respect to the rail in a first direction, and inhibits the relative axial displacement in a second direction opposite to the first direction.

Full Description:
BACKGROUND OF THE INVENTION  
         [0001]    There have always been inherent problems with the transportation and use of tools up and down a ladder. One known solution is to attach a container by means of a rope to a pulley, which is usually secured to a bracket at the top of the ladder. A person can place tools in the container and then raise or lower the tools by pulling on the rope. The disadvantage with this system is that the container is not sufficiently stable for the transportation of liquids in open top containers, such as paint cans. A further problem is that operation of this system is awkward while the person is on the ladder. Grasping the rope requires the person to let go of the ladder, thereby posing a potential safety hazard.  
           [0002]    Other solutions include an S hook for hanging a paint can on a ladder portion, or plastic trays that are hooked onto a rung. These systems can require the person to push away from the ladder to access a tool or other materials supported by these devices, thereby creating a potential safety concern.  
           [0003]    Another product is a saddle carrier having two bags connected by a middle portion, which can be hung around a rung of a ladder. The person first places the tools in the saddle carrier and then holds on to the carrier while climbing the ladder. The person then hangs the carrier around a selected rung upon reaching a desired height, thereby providing support for the tools at a selected vertical location. This method poses a potential safety hazard, as carrying of the carrier may interfere with the person&#39;s movements, while climbing or descending the ladder.  
           [0004]    Also available are “A” type ladders that have a platform attached at a fixed location. The platform provides a user on the ladder with a stable support for tools and paint containers when not in use. However, the person must climb the ladder while holding the tools in order to place them on the platform. This system also poses a potential safety hazard, as the carried tools may interfere with the person&#39;s movement while climbing the ladder. Another problem with this system is that the fixed platform may not always be located in a convenient location, while using the ladder.  
           [0005]    It is an object of the present invention to obviate or mitigate the above presented disadvantages.  
         SUMMARY OF THE INVENTION  
         [0006]    According to the present invention there is provided a tool carrier for use with a ladder. The assembly comprises a platform and a coupling mechanism to connect the platform to a rail of the ladder. The coupling mechanism includes a locking member engageable with the ladder to secure the carrier in a selected axial position along the rail. Axial displacement of the platform along the rail is such that the locking mechanism permits relative axial displacement of the assembly with respect to the rail in a first direction, and inhibits the relative axial displacement in a second direction opposite to the first direction.  
           [0007]    A further aspect of the invention provides a coupling apparatus for use with a ladder. The coupling apparatus comprises a body having a pair side portions connected to a back portion. The pair of side portions are placed in a spaced apart relationship to define an interior for receiving the rail. The coupling has a connector for securing the object to the body, and a locking mechanism to monitor relative axial displacement of the body with respect to the rail. The displacement is permitted by the locking mechanism in a first direction and inhibited in a second direction opposite to the first direction. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:  
         [0009]    [0009]FIG. 1 is a rear perspective view of a tool carrier coupled to a ladder;  
         [0010]    [0010]FIG. 2 is a plan view of a tray of the tool carrier of FIG. 1;  
         [0011]    [0011]FIG. 3 is a section  3 - 3  side view of FIG. 2;  
         [0012]    [0012]FIG. 4 is a perspective view of a coupling of FIG. 1;  
         [0013]    [0013]FIG. 5 is a section  5 - 5  end view of FIG. 4;  
         [0014]    [0014]FIG. 6 is a section  6 - 6  side view of the coupling of FIG. 4 in a closed position;  
         [0015]    [0015]FIG. 7 shows a side view of the coupling of FIG. 6 in an open position;  
         [0016]    [0016]FIG. 8 is an end view of FIG. 1;  
         [0017]    [0017]FIG. 9 is a further embodiment of FIG. 1; and  
         [0018]    [0018]FIG. 10 is a section  10 - 10  top view of FIG. 4. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]    Referring to FIG. 1, a tool carrier  8  comprises a tray  10  attached to a ladder  12  by a coupling  14 . The coupling  14  permits selective attachment of the tray  10  to a rail  16  of the ladder  12 , whereby the tray  10  is cantilevered to one side, preferably the right side. This arrangement provides a platform secured at a selected longitudinal location, which can be used by a person (not shown) on the ladder  12 . The tool carrier  8  can be employed to carry a variety of trade and household objects (not shown), such as but not limited to tools, paint, and paint brushes.  
         [0020]    The tray  10  is configured to facilitate the performance of common trade and household repairs at elevated locations, and has a pair of side walls  24 ,  26 , a front wall  28 , and a rear wall  30 . The walls  24 ,  26 ,  28 ,  30  extend from and are connected to a bottom wall  32  to form an open topped interior  34 . Internal dividing walls  36 ,  38  can be used to separate the interior  34  into separate compartments  35 ,  37 ,  39  for holding the objects. The tray  10  includes a series of holes  46  provided on a flange  27 , projecting from the wall  26 , to retain tools such as screwdrivers and pliers. A crevice  48  is located on the rear wall  30  to hold pieces of cloth, such as rags, and a circular depression  50  is located on the bottom  32  to facilitate placement of cylindrical containers in the interior  34  of the tray  10 , such as paint cans. The crevice can include an arcuate portion  49  in order to retain an extension cord (not shown), if desired.  
         [0021]    Referring to FIG. 3, a handle  18  includes an extended portion  40  to allow the user to carry the tray  10  approximately above its center of gravity and is connected to the rear wall  30  and the divider- 38  at either end, such as by adhesive, threaded fasteners, or a clip. A set of feet  42  are connected to the bottom  32  to provide stability for the tray  10 , when placed on a flat surface  44 .  
         [0022]    The tray  10  is detachably secured to the coupling  14  by a connector  52 , positioned on the side wall  24 , mateable with a corresponding connector  53  on the coupling  14 . The connector  52  has a pair of approximately parallel guide surfaces  54  extending from and along the side wall  24 . A plate  56  having a top edge  66 , a front edge  68 , and a bottom edge  70 , is connected adjacent to the guide surfaces  54  to form a pair of U-shaped tracks  58 . Referring to FIGS. 2 and 8, the tracks  58  are in a spaced apart relationship on a top and bottom of the connector  52 , are open at one end  60 , and are closed by an abutment surface  62  at the other end  64 .  
         [0023]    Referring to FIG. 4, the coupling  14  includes the complementary connector  53  formed on a backplate  74 , which extends between a pair of side walls  72 ,  73 . The connector  53  comprises a pair of L-shaped members  78 ,  80  secured to the back plate  74 , in a spaced apart relationship corresponding to that of the tracks  58  on the tray  10 . Runner portions  82  on the members  78 ,  80  are slidably received in the tracks  58  and rest against the guide surface  54 , when the connector  53  is coupled to the connector  52 , as shown in FIG. 8. The runner portions  82  are fully received in the tracks  58 , when an end face  84  of the members  78 ,  80  contacts the abutment surface  62 .  
         [0024]    Separation of the connectors  52 ,  53  is inhibited by a detent, formed by the engagement of a barb  86  located on the upper surface  88  (see FIG. 6) with a corresponding recess  90  located on the edge  70  of the plate  56  (see FIG. 3). An interference fit between the tracks  58  and the runners  82  can also be used to inhibit separation of the connector  53  from the connector  52 , once the coupling  14  is connected to the tray  10 . The guide surfaces  54  are inclined by approximately 11° to 20°, preferably 17°, with respect to the bottom wall  32 . This angle of inclination  59  also helps to retain the connection of the tray  10  and the coupling  14 , by the connectors  52 ,  53 , due to cooperation of the weight of the tray  10  and contact between the end face  84  and the abutment surface  62 . When the carrier  8  is connected to the ladder  12 , an angle  59  that is too shallow may facilitate the coupling  14  becoming disconnected from the tray  10  in a transverse direction to the ladder axis. If the angle  59  is too steep, the coupling  14  may become disconnected in an axial direction during use of the carrier  8 .  
         [0025]    Referring to FIG. 4, the side walls  72 ,  73  of the coupling  14  are in a spaced apart relationship corresponding to a width of the rail  16 . The coupling  14  has a control arm  76  extending between the side walls  72 ,  73 , to form an interior  75  which receives the rail  16  when the coupling  14  is attached to the ladder  12 , as shown in FIG. 1. Dimensions of the interior  75  should be somewhat larger than the exterior dimensions of side portions  94 ,  95  and face portion  100  of the rail  16 , in order to facilitate connection of the coupling  14  and the rail  16 . The arm  76  is preferably angled by between 30° and 60°, preferably 45°, with respect to a base surface  79  of the coupling  14 .  
         [0026]    The coupling  14  can have a series of nodules  98  positioned on the back plate  74 , to provide clearance between a face portion  100  of the side rail  16  and the back plate  74 . This arrangement helps to reduce friction between the side rail  16  and the back plate  74 . The back plate  74  also has scallops  81 , which can be used to accommodate protrusions on the face  100  such as rivet or bolt heads. The side walls  72 ,  73  of the coupling  14  have U-shaped channels  92  formed therein, which also provide clearance of a face  96  to accommodate any protrusions on the side portions  94 ,  95 .  
         [0027]    The axial position of the coupling  14  on the rail  16  is controlled by the arm  76 . Referring to FIGS. 4, 5 and  10 , the arm  76  is pivotally connected at one end portion  102  to an arcuate portion  104 , by a pin joint  106 . An increased thickness of the arm  76  near the pin joint can be used to inhibit breakage of the arm  76 . The pin joint  106  includes a torsion spring  107  located in a cavity formed by opposing bores  134 ,  136 . The spring can be a counterclockwise torsion spring, if desired. A threaded bolt  138  is employed to hold the components  104  and  76  together, once assembled. The spring  107  is wound around the bolt  138  and the spring ends  140  are received by corresponding bores in the components  76 ,  104 . This arrangement biases an end portion  108  of the arm  76  towards a latch arm  110 , which is connected to the side wall  72 .  
         [0028]    The latch arm  110  is received in a notch  112  formed on an end face  114  of the end portion  108 . Travel of the arm  76  towards the latch arm  110  is inhibited by contact of the notch  112  against the latch arm  110 , which places the arm  76  in a closed position. A surface  116  of the arm  76  is used to abut the rung  22 , shown in ghosted view in FIG. 6. In this position, further movement of the tool carrier  8  down the ladder  12  is inhibited.  
         [0029]    In operation of the tool carrier  8 , the coupling  14  is releasably secured to the tray  10  by inserting the runner portions  82  in the tracks  58 , as shown in FIG. 8. The coupling  14  is connected to the rail  16  by first contacting a knob  113  on the end  108  against the side portion  95 , and then displacing the side wall  72  of the coupling  14  towards the side portion  94  of the ladder  12 . This displacement rotates the arm  76  away from the latch arm  110 , thereby providing access to the interior  75  by the rail  16 . Once the side walls  72 ,  73  are adjacent to the corresponding side portions  94 ,  95 , the back plate  74  can be mated to the face  100  of the rail  16 , thereby receiving the rail  16  by the interior  75  of the coupling  14 . This arrangement places the knob  113  out of contact with the side portion  95 , thereby causing the arm  76  to rotate into return contact with the latch arm  110  to enclose the rail  16  in the interior  75 .  
         [0030]    A user can climb the ladder  12  by holding the handle  18  of the tray  10  in one hand, grasping a rail  20  of the ladder  12  with the other hand, and climbing each successive rung  22  with alternating feet. This climbing arrangement can provide a three point contact between the user and the ladder  12  during use of the tool carrier  8 .  
         [0031]    Axial movement of the tool carrier  8  along the rail  16  is periodically interrupted by the series of rungs  22 . Referring to FIG. 7, as the coupling  14  is displaced along the ladder  12  (shown in ghosted view) in a direction indicated by arrow  118 , the arm  76  encounters the rung  22  and pivots away from the latch arm  110 . Once the arm  76  has moved past the rung  22 , the spring  107  will bias the end  108  into return contact with the latch arm  110 . Once the latch arm  110  is received by the notch  112 , the arm  76  is in the closed position. Referring to FIG. 6, the rung  22  is now positioned under the arm  76 . In this position, the rung  22  is used to inhibit displacement of the coupling  14  and attached tray  10  back down the ladder  12  due to the influence of gravity. The user can now let go of the handle  18  and interact with the tool carrier  8 , as its selected axial position is maintained by the arm  76 . The location of the tool carrier  8  can be adjusted axially along the ladder  12  by repeating the above described operation.  
         [0032]    The cantilevered arrangement of the tool carrier  8  with respect to the rail  16  facilitates movement of the user up and down the ladder  12 , since the tray  10  and retained tools are positioned adjacent to the rungs  22  and rails  16 ,  20 . This arrangement does not push the user backwards away from the ladder  12  while climbing thereon, as can be the case when carrying tools close to the user&#39;s body.  
         [0033]    Detachment of the coupling  14  and the attached tray  10  from the rail  16  can be accomplished by rotating the arm  76  of the coupling  14 , until the arm  76  is sufficiently positioned to the side of the interior  75 . This can be accomplished either manually with the user&#39;s hand, or automatically by contacting the arm  76  with the rung  22 . Once the arm  76  is rotated away from the latch arm  110 , the coupling  14  can be laterally displaced away from the rail  16 , thereby removing the back plate  74  from in contact with the face  100  of the rail  16 . This results in the rail  16  and coupling  14  being disengaged from one another, whereby the user can carry the tool carrier  8  down the ladder  12 . It should be noted that the tray  10  could be disengaged from the coupling  14  instead, to allow the user to transport the tray  10  separately down the ladder  12 .  
         [0034]    The tray  10  and coupling  14  are preferably made of a rigid material, such but not limited to as metal, fiberglass, or plastic. The connectors  52 ,  53  could be replaced by a permanent connection between the coupling  14  and the tray  10 , such as but not limited to adhesive, mechanical fasteners such as screws or bolts, or the components  14 ,  10  could be integrally molded to one another.  
         [0035]    An application of the tool carrier  8  includes a roller paint tray  120  supported by the tray  10 , as shown in FIG. 9. The paint tray  120  has two compartments  122 ,  124  joined by a resilient joint  126 . The compartment  122  is used to hold poured paint and the compartment  124  is used to hold a paint roller or brush (not shown), with the roller handle (not shown) accommodated in a furrow  130  adjacent to the handle  18 . The paint tray  120  is supported by the tray  10  when the compartment  122  is placed in the compartment  39 . A pair of tabs  128  can be employed to hook onto the dividing wall  38  for further stability of the paint tray  120  when positioned in the tray  10 . A wedge  132  on the handle  18  can be employed to mate with a corresponding edge  134  located on the tray  120  for further support, if desired. The paint tray  120  is preferably made of plastic and may be a disposable product, if desired. The joint  126  should be sufficient rigid so as to support the weight of the paint roller when placed in compartment  124 .  
         [0036]    Although the invention has been described with reference to certain specific embodiments, various modifications thereof will be apparent to those skilled in the art without departing from the spirit and scope of the invention as outlined in the claims appended hereto.

Technology Classification (CPC): 4