Patent Publication Number: US-2023139449-A1

Title: Work Platform and Method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a nonprovisional of U.S. Provisional Pat. Application Serial No. 63/273,127 filed Oct. 28, 2021; and is a continuation-in-part of U.S. Pat. Application Serial No. 17/863,220 filed on Jul. 12, 2022, both of which are incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention is related to an extendable work platform which, in a closed position, can be used as a scaffold. (As used herein, references to the “present invention” or “invention” relate to exemplary embodiments and not necessarily to every embodiment encompassed by the appended claims.) More specifically, the present invention is related to an extendable work platform, which in a closed position, can be used as a scaffold having a linkage which engages support structures to securely and stably hold the work platform in the closed position as a scaffold. 
     BACKGROUND OF THE INVENTION 
     This section is intended to introduce the reader to various aspects of the art that may be related to various aspects of the present invention. The following discussion is intended to provide information to facilitate a better understanding of the present invention. Accordingly, it should be understood that statements in the following discussion are to be read in this light, and not as admissions of prior art. 
     A user commonly must adapt to the needs of the work environment. It is typically desirable to have a single product serve more than one function rather than to have multiple separate products having to serve multiple functions. In certain instances, a user requires a work platform and separately, a scaffold. It would be advantageous to have a single apparatus which serves as a work platform and also serves as a scaffold which can be securely engaged with a support structure to support the scaffold at a desired height without interfering with a user. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention pertains to a work platform. The work platform comprises a plank which telescopes to a desired width. The work platform comprises a first leg assembly rotatably attached adjacent to a first end of the plank. The work platform comprises a second leg assembly rotatably attached adjacent to a second end of the plank. The platform is in an open position when the plank is supported by the first leg assembly and second leg assembly and the first leg assembly and second leg assembly form an angle greater than 25 degrees with the plank. The platform is in a closed position when the first leg assembly and second leg assembly are adjacent to and in parallel with the plank. 
     The present invention pertains to a method for using a work platform. The method comprises the steps of extending a plank which telescopes of the work platform to a desired width determined by a distance between a first support structure and a second support structure separate and apart from the first support structure. There is the step of moving a first leg assembly of the work platform which is rotatably attached adjacent to a first end of the plank and a second leg assembly of the work platform which is rotatably attached adjacent to a second end of the plank from an open position, where the plank is supported by the first leg assembly and second leg assembly on ground and the first leg assembly and second leg assembly each form an angle greater than 25 degrees with the plank, to a closed position, where the first leg assembly and second leg assembly are adjacent to and in parallel with the plank. There is the step of placing the first end of the plank on the first support structure and the second end of the plank on the second support structure when the plank and the first leg assembly and second leg assembly are in a closed position. 
     The present invention pertains to a method for producing a work platform. The method comprises the steps of placing first supports of a first portion into hollow deck supports of a deck. The first supports able to move in and out of the deck supports. There is the step of placing a hook into one first support of the first supports, the hook able to move in and out of the one first support. 
     The present invention pertains to a method for using a work platform. The method comprises the steps of extending a plank which telescopes of the work platform to a desired width determined by a distance between a first support structure and a second support structure separate and apart from the first support structure. There is the step of moving a first leg assembly of the work platform which is rotatably attached adjacent to a first end of the plank and a second leg assembly of the work platform which is rotatably attached adjacent to a second end of the plank from an open position, where the plank is supported by the first leg assembly and second leg assembly on ground and the first leg assembly and second leg assembly each form an angle greater than 25 degrees with the plank, to a closed position, where the first leg assembly and second leg assembly are adjacent to and in parallel with the plank. There is the step of extending a first linkage from adjacent the first end of the plank. There is the step of engaging the first linkage with the first support structure and a second linkage adjacent the second end of the plank on the second support structure when the plank and the first leg assembly and second leg assembly are in a closed position to securely and stably hold the plank to the first support structure. 
     The present invention pertains to a method for producing a work platform. The method comprises the steps of rotatably attaching a first leg assembly to a first end of a plank of the work platform. There is the step of attaching a first linkage to a first leg of the first leg assembly, the first linkage adapted to secure the work platform to a first support structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    shows the plankform with the legs folded and the deck in the shortest retracted condition. 
         FIG.  2    shows the plankform with the legs extended. 
         FIG.  3    shows the plankform in the work platform mode and the deck  38  extended to its maximum length. 
         FIG.  4    shows the plankform when used as a plank in its retracted condition. 
         FIG.  5    shows the plankform when used as a plank in its extended condition. 
         FIG.  6    shows an additional feature of this invention. Hooks are mounted in the plankform at both ends which can be moved to a stowed position. 
         FIG.  6 A  is a sectional view of A of  FIG.  6   . 
         FIG.  7    shows the hooks mounted in the plankform at both ends which can are moved to a deployed position. 
         FIG.  7 A  is a sectional view of A of  FIG.  7   . 
         FIG.  8    shows how the hooks engage with the steps of stepladders when the plankform is in the retracted position. 
         FIG.  8 A  is a sectional view of A of  FIG.  8   . 
         FIG.  9    shows how the hooks engage with the steps of stepladders when the plankform is in the extended position. 
         FIG.  10    shows a further embodiment in which springs tend to cause the hooks to retract and a handle with its own hooks connects the ends of the hooks. 
         FIG.  10 A  is a bottom perspective view of the first portion with the handle and hooks in a retracted position. 
         FIG.  11    is a bottom view of the embodiment of  FIG.  10   . 
         FIG.  11 A  is an overhead perspective view of the first portion with the handle and hooks in an extended position 
         FIG.  12    shows the plankform of  FIG.  10    laid onto its supports. 
         FIG.  13    shows how recesses are formed in the legs which are positioned to engage the plankform support surfaces when the legs are in the folded position. 
         FIG.  13 A  is a side view of a leg with a recess in a closed position. 
         FIG.  14    shows how recesses are formed in the legs which are positioned to engage the plankform support surfaces when the legs are in the open position. 
         FIG.  14 A  is a side view of a leg with a recess in the open position. 
         FIG.  15    shows the plankform supported by a ladder with the recesses engaged with the ladder steps. 
         FIG.  16    shows the linkage attaching to a ladder rung via the hooks that extend from the legs of the plankform while in plank mode. 
         FIG.  17    shows the linkage fully deployed with the plank hidden. 
         FIG.  18    shows the hook retracted into the rail when it is not in use. 
         FIG.  19    shows the hook retracted into the leg when it is not in use. 
         FIGS.  20 ,  21  and  22    show the sequence of the hook being moved into the stowed position. 
         FIG.  23    shows straps attached to the plankform which pass around a rung or ladder jack to prevent the plankform from coming off its supports. 
         FIG.  24    shows straps attached to the plankform which pass around a rung or ladder jack to prevent the plankform from coming off its supports. 
         FIG.  25    shows a single strap in which the strap assembly is attached directly to the plank portion of the plankform instead of to the legs. 
         FIG.  26    shows the strap assemblies on the legs. 
         FIG.  27    shows the strap assembly on the plank surface. 
         FIG.  28    shows the end handle design comprised of a space for the user to put their hand and grab onto an ergonomically designed handle bar. 
         FIG.  29    shows a buckle for a strap. 
         FIG.  30    shows a buckle for a strap. 
         FIG.  31    shows a buckle for a strap. 
         FIG.  32    shows a buckle for a strap. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings wherein like reference numerals refer to similar or identical parts throughout the several views, and more specifically to  FIGS.  1 - 5    thereof, there is shown a work platform  10 . The work platform  10  comprises a plank  12  which telescopes to a desired width. The work platform  10  comprises a first leg assembly  14  rotatably attached adjacent to a first end  16  of the plank  12 . The work platform  10  comprises a second leg assembly  18  rotatably attached adjacent to a second end  20  of the plank  12 . The platform is in an open position when the plank  12  is supported by the first leg assembly  14  and second leg assembly  18  and the first leg assembly  14  and second leg assembly  18  form an angle greater than 25 degrees with the plank  12 , as shown in  FIGS.  2  and  3   . The platform is in a closed position when the first leg assembly  14  and second leg assembly  18  are adjacent to and in parallel with the plank  12 , as shown in  FIGS.  1 ,  4  and  5   . 
     The platform may include a first linkage  22  which extends from adjacent the first end  16  of the plank  12  adapted to engage a first support structure  24  to securely and stably hold the plank  12  to the first support structure  24 , as shown in  FIGS.  6 ,  6 A,  7  and  7 A,  8  and  9   . The first linkage  22  may be a first hook  26  which extends from the first end  16  of the plank  12 . The first hook  26  may be part of a handle  28  which extends from the first end  16  of the plank  12 , as shown in  FIGS.  10 ,  10 A,  11 ,  11 A and  12   . The platform may include a spring  30  which biases the handle  28  to a closed position with the plank  12  when the first hook  26  is apart from the first support structure  24 . Alternatively, first leg assembly  14  may include a first leg  32  having a first recess  34  which is adapted to fit onto an engage the first support structure  24 , as shown in  FIGS.  13 ,  13 A,  14 ,  14 A and  15   . 
     The first leg assembly  14  may include a second leg  35  in parallel with and in spaced relation with the first leg  32 , as shown in  FIGS.  2  and  3   . There may be a step  70  extending between and attached to the first leg and the second leg. The second leg assembly  18  may include a first leg and a second leg in parallel with and in spaced relation with the first leg of the second leg assembly  18 , and may have a step extending between and attached to the first leg and the second leg of the second leg assembly  18 . The first and second leg assemblies may be rotatably attached to the plank so the legs are disposed outside of the perimeter of the plank. See U.S. Pat. 10,848,858, incorporated by reference herein, for a description of leg assemblies which may be rotatably attached to the plank so the legs are disposed outside of the perimeter of the plank. 
     The present invention pertains to a method for using a work platform  10 . The method comprises the steps of extending a plank  12  which telescopes of the work platform  10  to a desired width determined by a distance between a first support structure  24  and a second support structure  36  separate and apart from the first support structure  24 . There is the step of moving a first leg assembly  14  of the work platform  10  which is rotatably attached adjacent to a first end  16  of the plank  12  and a second leg assembly  18  of the work platform  10  which is rotatably attached adjacent to a second end  20  of the plank  12  from an open position, where the plank  12  is supported by the first leg assembly  14  and second leg assembly  18  on ground and the first leg assembly  14  and second leg assembly  18  each form an angle greater than 25 degrees with the plank  12 , to a closed position, where the first leg assembly  14  and second leg assembly  18  are adjacent to and in parallel with the plank  12 . There is the step of placing the first end  16  of the plank  12  on the first support structure  24  and the second end  20  of the plank  12  on the second support structure  36  when the plank  12  and the first leg assembly  14  and second leg assembly  18  are in a closed position. 
     The placing step may include the steps of engaging a first linkage  22  from adjacent the first end  16  of the plank  12  with the first support structure  24 , and engaging a second linkage  23  from adjacent the second end  20  of the plank  12  with the second support structure  36  so the plank  12  is securely and stably held to the first and second support structures  24 ,  36 . The engaging the first linkage  22  step may include the step of moving a first hook  26  outwards from the first end  16  of the plank  12 . The engaging the second linkage  23  step may include the step of moving a second hook  27  outwards from the first end  16  of the plank  12 . Alternatively, the placing step may include the step of engaging a first recess  34  of a first leg of the first leg assembly  14  and a second recess  33  of a second leg of the first leg assembly  14  with the first support structure  24  so the plank  12  is securely and stably held with the first and second port structures. The first support structure  24  may be a rung of a ladder. 
     The present invention pertains to a method for producing a work platform. The method comprises the steps of placing first supports of a first portion into hollow deck supports of a deck, the first supports able to move in and out of the deck supports. There is the step of placing a hook into one first supports of the first supports, the hook able to move in and out of the one first support. 
     This invention is an extendable work platform  10  with folding legs which can also be used as a telescoping plank  12  between supporting structures when the legs are folded, as shown in  FIGS.  1 - 5   . The width of the plank  12  enables it to be placed between the legs of conventional ladders. The invention is a combination of an extendable plank  12  with leg assemblies which can be used as a work platform  10 , or as a scaffold placed between two support structures, such as to ladders on their steps  65 , with the leg assemblies folded up, and is called a plankform  10 . The plankform  10  supports at least 250 pounds of load in the open extended position, and even more than 500 pounds of load without failing when it is in the open extended position or being used as a scaffold in the extended position and supported on either side, as described herein, preferably by a step  65  of a first ladder and a step  65  of a second ladder. 
     In one embodiment, retractable hooks extend from the end of the plank  12  which fit over the rungs, steps, etc., which the plank  12  will rest on, as shown in  FIGS.  6 - 9   . 
     In another embodiment, the hooks are spring-loaded which draw the plank  12  into snug engagement with its supports, as shown in  FIGS.  10 - 12   , with or without a handle  28 . 
     In another embodiment, recesses are formed in the plankform 10 legs which are used to engage the support, as shown in  FIGS.  13 - 15   . 
     This invention enables the user to adapt to the needs of the work environment without needing two separate products. Its length in either mode of use is adjustable between 4′ and 8′ which enables the user to work in a large area without having to relocate his or her plank  12 /work platform  10 . 
     Additionally, the embodiment of extendable hooks permits 100% of the plank  12  standing area to be used, and the hooks provide very solid engagement with the plank  12  support surface. 
       FIG.  1    shows the plankform  10  in the closed position with the legs folded and the plank  12  in the shortest retracted position. In this state, the plankform  10  can be easily transported or stored. The plank  12  is preferably comprised of a deck  38 , a first portion  40  which extends and retracts from a first side  41  of the deck  38 , and a second portion  42  which extends and retracts from a second side  43  of the deck  38 , as shown in  FIG.  3   . The deck  38  itself is comprised of a plurality of hollow deck supports  44  of the same dimensions, having either a rectangular or C shaped cross-section, which are in parallel and adjacent with each other and fixed together. Here, there are four deck supports  44  attached together, with two interior deck supports  44  and two exterior deck supports  44 . On either side of the outside of both exterior deck supports  44  is a side bracket  46  which extends the length of the exterior deck support it is alongside. Extending perpendicular from and attached adjacent each end of the side brackets  46  is a top deck bracket  48 . The top deck bracket  48  fits over the deck supports  44  and does not block any portion of the hollow interior of the deck supports  44 . Adjacent one end of each side bracket  46  is fixed a lock  50  to lock the first portion  40  and the second portion  42  at a desired position relative to the deck  38 . An example of a type of lock that can be used as described in U.S. Pat. 5,067,589, incorporated by reference herein. A flat serrated metal plate  52  may be positioned atop the deck supports  44  and attached to both side brackets  46 . 
     The first portion  40  is comprised of four first supports  54  which are attached together like the deck supports  44 , although each of the first supports  54  has a cross-section which is smaller than the cross-section of the deck supports  44  so the first supports  54  can fit into and slide in and out of the deck supports  44 . One first support fits into one deck support. The first supports  54  are aligned and fitted into the deck supports  44  at the first side  41  of the deck  38 . There may be one or more top first brackets  56  fitting over the first supports  54  and attached to the first supports  54  between the two external first supports  54  to fix the first supports  54  together. 
     There are locking holes  58  present at regular intervals on the outside of the external first support which is adjacent the lock  50  on the side bracket  46 . The lock  50  fits into the desired locking hole to lock the first portion  40  at a desired position relative to the deck  38 . The second portion  42  is comprised of four second supports  60  and are configured and operate in the same way as the first portion  40  and with respect to the deck  38 . There may be one or more top second brackets  57  fitting over the second supports  60  and attached to the second supports  60  between the two external second supports  60  to fix the second supports  60  together. 
     The first leg assembly  14  is rotatably attached adjacent to the outer end  62  of the first portion  40  and the second leg assembly  18  is rotatably attached adjacent to the outer end  64  of the second portion  42 . The length of the first supports  54  and the length of the second supports  60  are generally slightly less than half the length of the deck supports  44  so when the first and second supports  54 ,  60  are moved into the retracted position, the first and second supports  54 ,  60  do not block each other from fitting all the way into the deck supports  44 . The top first bracket also may act as a stop when it abuts the top deck bracket  48  at the first side  41  of the deck  38  when the first portion  40  is moved into the deck  38 . In the same way the top second bracket may also act as a stop when it abuts the top deck bracket  48  at the second side  43  of the deck  38  when the second portion  42  is moved into the deck  38 . 
       FIG.  2    shows the plankform  10  with the legs extended and the plank  12  in a retracted position. In this mode, the plankform  10  can be used as a conventional work platform  10 . 
       FIG.  3    shows the plankform  10  in the work platform  10  mode and the plank  12  in an extended position where it is extended to its maximum length. 
       FIGS.  4  and  5    show the plankform  10  when used as a scaffold with the plank  12  in its retracted and extended conditions, respectively. It is shown resting on the steps  65  of stepladders but could also be used with roof jacks, scaffolds, etc., in the manner which conventional planks are used. 
       FIGS.  6 ,  6 A,  7  and  7 A  show an additional feature of this invention. Hooks are mounted in the plankform  10  at both ends which can be moved to a stowed position, as shown in  FIGS.  6  and  6 A , or a deployed position, as shown in  FIGS.  7  and  7 A . Notice that the hooks have overhanging ends  66 , as shown in  FIG.  7 A . In this embodiment, there are four separate hooks, each independent from the other. There are two hooks which extend from the outer end  62  of the first portion  40  and two hooks which extend from the outer end  64  of the second portion  42 . Each hook of the first portion  40  fits in and is able to slide back and forth in an external first support, and each hook of the second portion  42  fits in and is able to slide back and forth in an external second support. Each hook is formed of a stem  68  which fits into the respective external first or second support, and an overhanging end  66 , which is a flat rectangular plate attached to the stem  68  which extends below the bottom of the stem  68 . In a stowed position, as shown in  FIG.  6    and  FIG.  6 A , the stem  68  of each hook fits completely within the respective first or second support, and the overhanging end  66  fits on the surface of the respective outer end of the first or second portion. The overhanging end  66  acts as a stop, preventing the hook from going too far into the respective external first or second support, catching on the outer end of the respective portion. Extending up from the base  71  of the outer end  62 , in the path of the hook, is a screw against which the inner end  87  of the stem  68  contacts, which acts as a stop that prevents the stem  68  from coming out of the first or second portion when the hook is pulled out and deployed, as shown in  FIGS.  7  and  7 A . Extending through the base  71  of the outer end  62  are the levers  73  of the hinge release mechanism, as shown in  FIG.  10   , which withdraw locking bars from the hinges of the leg assemblies, as is well known in the art. 
       FIGS.  8  and  9    show how the hooks engage with the steps  65  of stepladders. When used this way, the full length of the plankform  10  can be used by the user and the plankform  10  is securely held in place by the overhanging ends of the hooks.  FIG.  8    shows the plankform  10  in the retracted position with the hooks deployed from the first portion  40  positioned on a step  65  at a desired height of a first ladder, and with the hooks deployed from the second portion  42  positioned on a step  65  at the same height of a second ladder. As shown in  FIG.  8 A , the stems  68  of the hooks rest flat on the top surface  74  of the steps  65  and the overhanging ends extend down from the top surface  74  of the steps  65  and ideally contact the interior sides  75  of the steps  65 . In this way, the plankform  10  stably and securely is positioned at a desired height with the support of the first and second ladders so users may climb on top of the plankform  10 . In the same way, the plankform  10  in an extended position is supported by the first and second ladders, as shown in  FIG.  9   . The hooks will also permit the plankform  10  to engage ladder jacks, roof jacks, scaffolds, etc. 
       FIGS.  10 ,  10 A,  11  and  11 A  show a further embodiment in which springs  30  tend to cause the hooks to retract and a handle  28  with its own hooks connects the ends of the hooks. In the further embodiment, both hooks on the same portion of the plankform  10  are attached to a handle  28  at their overhanging ends. The handle  28  is preferably one piece with a base  77  that is flat and is welded to the overhanging ends and extends between the two hooks and preferably not beyond them. At the bottom of the base and extending below the overhanging ends in the first and second portions are arcs  79  which curve downwards and inwards from the base  77 . At the top of the base, preferably extending along the length of the base  77  is a handle flange  81  which angles outwards and downwards, between 10° and 70° and preferably about 30° from the base  77 . 
     The stems  68  of the hooks engage with and fit into the supports in the same way as they do in the embodiment described above where the hooks are separate and apart from each other. However, in this embodiment, the internal end  83  of each stem  68  is fixed to the outer end  85  of a handle spring, as shown in  FIG.  10    and  FIG.  11   . The inner end  87  of the handle spring is fixed to a spring bracket  89  extending down from the inner surface of the respective support of the first or second portions. In use, the user pulls the handle  28  outward, extending the hooks against spring force. When the plankform  10  has been laid onto its supports as seen in  FIG.  12   , the handle  28  is released which allows the hooks to retract by the force of the springs  30  and the arcs  79  to positively engage the step  65  of the ladder. The arcs  79  of the handle  28  fit under and contact the bottom surface  91  of the step  65 , with the base  77  contacting the interior side  75  of the step  65  to securely and stably hold the plankform  10  in the desired position. The springs  30  act as stops preventing the hooks from being pulled out of the first supports  54 , or second supports  60 .  FIG.  10    shows a bottom view of the first portion  40  with the handle  28  and hooks in a retracted position.  FIG.  11    shows a bottom view of the first portion  40  with the handle  28  and hooks in an extended position.  FIG.  10 A  is a bottom perspective view of the first portion  40  with the handle  28  and hooks in a retracted position.  FIG.  11 A  is an overhead perspective view of the first portion  40  with the handle  28  and hooks in an extended position.  FIG.  12    is a bottom perspective view of the first portion  40  with the handle  28  extended and engaged with the step  65 . 
       FIGS.  13 ,  13 A,  14  and  14 A  show yet another embodiment with recesses formed in the legs which are positioned to engage the plankform  10  support surfaces when the legs are in the closed position.  FIG.  15    shows the plankform  10  supported by a ladder with the recesses engaged with the ladder steps  65 . 
     In this embodiment, there are no hooks in the plank  12 . Instead, recesses adjacent the top of each leg serve to stabilize the plank  12  on the steps  65  of the support ladders. Each recess has a shape which conforms with the top and interior and exterior sides of the step  65 . Each recess has a long portion  90  which is straight and rests on the top surface of the step  65 . At each end of the long portion  90 , a side portion  92  extends perpendicularly from the long portion  90 . The side portion  92  adjacent the top of the leg fits over the interior side  75  of the step  65  and the other side portion  92  fits over the exterior side  94  of the step  65  when the plankform  10  is placed on the steps  65 , as shown in  FIG.  15   . The side portion  92  adjacent the top of the leg hooks with the interior side  75  of the step  65 , preventing the plank  12  from being pulled away from the step  65 , and the other side portion  92  hooks with the exterior side  94  of the step  65 , which prevents the plank  12  from moving toward the interior of the ladder, thus preventing plank  12  from moving forward or back relative to the step  65 . 
     A hinge portion  96  positioned opposite the recess adjacent the side portion  92  at the top of the leg, has a bolt  98  extending through it which rotatably attaches the leg to the plank  12  and serves as a pivot axis. The leg itself has an upper part  100  from about the top step of the respective leg assembly and has a width about half the width of the lower part  102  of the leg so the leg does not block the step  65  from receiving the recess. The recess itself with the hinge portion is part of a leg plate  104  which has a lower portion  106  that extends down from the lower side portion  92  and which conforms with the outer circumference of the flange and webs of the lower part  102  of the leg. The outer circumference of the flange and the webs of the leg plate  104  essentially form a C shape which matches the C shape of the outer circumference of the lower part  102  of the leg. The lower portion  106  is riveted to the lower part  102  of the leg adjacent where the top step is attached to the leg. A central portion  108  of the leg plate  104  which extends upwards from the lower portion  106  in between the recess and the hinge portion  96 , is riveted to the upper part  100  of the leg.  FIG.  13    shows a perspective view of the legs with recesses in the closed position.  FIG.  13 A  is a side view of a leg with a recess in a closed position.  FIG.  14    shows a perspective view of the legs with recesses in an open position.  FIG.  14 A  is a side view of a leg with a recess in the open position. 
     A hook attachment technique, as shown if  FIGS.  16 - 22   , comprises at least a first hook  26  that rotates out of a first leg  32  of the first leg assembly  14  and is adjustable to grip the intended rung  65  or ladder jack. The first hook  26  can be rotated back in to a stowed position during work platform  10  mode, allowing the user to ascend or descend from the work platform  10  while utilizing the step features on the legs of the first or second leg assemblies and not be a tripping hazard. It is intended to secure the work platform  10  in plank  12  mode to a step ladder or ladder jack for device stability while the user is working on top of the work platform  10  in plank  12  mode. It is also used as a device that secures the work platform  10  in plank  12  mode to ladder jacks to prevent uplift due to wind. 
     A strap attachment technique, as shown in  FIGS.  23 - 27   , comprises a strap assembly  122  having a strap  126  that wraps around the rung  65  of a step ladder or a ladder jack. It can be attached to either the legs or the plank  12  itself. The strap  126  can be tightened by a cinching system, ratcheting system, a hooking method, or a Velcro type of hook and loop fastener.  FIGS.  29 - 32    show various buckles and straps that may be used. It is intended to secure the work platform  10  in plank  12  mode to a step ladder or ladder jack for device stability while the user is working on top of the work platform  10  in plank  12  mode. It also functions to secure the work platform  10  in plank  12  mode to step ladders or ladder jacks to prevent uplift due to wind. 
     An end handle  133 , shown in  FIG.  28   , is conveniently located at both ends of the work platform  10 . It can be used to carry the work platform  10 . It can be used to help the user pull the work platform  10  from a truck bed. It can also be used to help the user adjust the telescoping length of the work platform  10 . 
     The novelty of the strap and hook techniques is that the work platform  10  can be mechanically secured to a step ladder or ladder jack by unique built-in features. Typically, today if a user wants to secure a plank  12 , he or she does so with his or her own equipment such as rope or bungee cords. 
     The novelty of the end handle  133  is that present adjustable planks do not have a handle which helps the user to adjust the length and is also used to carry the plank  12 . 
     In regard to these additional embodiments, the hooks and straps provide very solid engagement with the plank  12  support surfaces. 
     With reference to  FIGS.  16 - 22   , the first hook  26  may be mounted in a first leg  32  of the first leg assembly  14 . The first hook  26  moves between a stowed position and a deployed position. The first hook  26  has an overhanging end  66  and a stem  68 , as shown in  FIG.  20   . The stem  68  fits into the first leg  32  in the stowed position, as shown in  FIGS.  18 ,  19  and  22   . The platform  10  may include a spring  30  which biases the first hook  26  toward a closed position with the plank  12  when the first hook  26  is apart from the first support structure  24 , and tensions the first hook  26  with the first support structure  24  to positively engage the first support structure  24   and facilitate a secure and tight fit of the first hook  26  with the first support structure  24 . See  FIGS.  19 - 22   . 
     An outer end  62  of the spring  30  may be fixed to a first spring bracket  89  extending down from an inner surface  110  of the of the first leg  32 . When the first hook  26  is pulled outward and the first hook  26  has been engaged with the first support structure  24 , the first hook  26  is released which allows the first hook  26  to retract by the force of the spring  30  and positively engage the first support structure  24 . The first linkage  22  may include a rod  112  which extends through and is in sliding engagement with the spring bracket  89 . The rod  112  has a front end  114  disposed adjacent the first side  41  of the plank  12 . The first hook  26  is engaged with the rod  112  adjacent the front end  114  of the rod  112 . The first hook  26  is disposed perpendicular with the rod  112  in the deployed position and disposed parallel with the rod  112  in the stowed position. The spring  30  is disposed about the rod  112 . 
     The overhanging end  66  may fit under and contact a bottom surface  91  of a rung  65  of the first support structure  24  and the stem  68  contacts an interior side  75  of the rung  65  to securely and stably hold the plankform  10  to the first support structure  24 , as shown in  FIG.  16   . The first linkage  22  may include a pin  116  that rotatably attaches the hook to the rod  112 . The pin  116  extends through adjacent an end of the stem  68  opposite the overhanging end  66  and into the rod  112 . An inner end  87  of the spring  30  may be attached to the rod  112 . The rod  112  may rotate when the hook is parallel to the rod  112  to position the hook in the retracted position in the first leg. The platform may include a second spring bracket  89  extending down from the inner surface  110  of the of the first leg through which the rod  112  extends. 
       FIG.  16    shows the first hook  26  attaching to a ladder rung  65  via the first and second hooks that extend from the legs of the plankform  10  while in plank  12  mode. 
       FIG.  17    shows the first hook  26  fully deployed with the plank  12  hidden. 
       FIG.  18    and  FIG.  19    show the first hook  26  retracted into the first leg  32  when it is not in use. 
       FIGS.  20 ,  21  and  22    show the sequence of the first hook  26  being moved into the stowed position. The first hook  26  is attached to the horizontal rod  112  by a pin  116 . This pin  116  connection allows the first hook  26  to be pivoted to a horizontal position, as seen in  FIG.  21   . Once it is horizontal, the first hook  26  and rod  112  together may be rotated about the long axis of the rod  112  to the stowed position in  FIG.  22   . Also seen in these figures is a coil spring surrounding the horizontal rod  112 . This spring  30  urges the rod  112  and first hook  26  to move to the right as viewed in these figures. This spring  30  action causes the first hook  26  to firmly grip the ladder rungs, thus taking up any slack between the plank  12  and its supports and preventing the plankform  10  from inadvertently coming off its supports due to wind gusts. The second linkage  23 , including the second hook  27 , operates the same way as the first linkage  22 , including the first hook  26 . 
     Alternatively, the first linkage  22  may include a first strap assembly  122  which extends from the first end  16  of the plank  12 , as shown in  FIGS.  23 - 27   . The first strap assembly  122  may be connected to the first leg  32  of the first leg assembly  14 . The strap assembly  122  may comprise a base  124  which is attached to the first leg and to a fixed end  128  of the strap  126 . The strap assembly  122  may include a buckle  132  attached to the base  124  adjacent to the fixed end  128  of the strap  126 . A free end  130  of the strap  126  may be disposed in and held by the buckle. The strap  126  it is adapted to be positioned about the rung  65  to hold the plank  12  securely to the first support structure  24 . 
       FIGS.  23  and  24    show the strap concept comprising strap assemblies  122  attached to the plankform  10  which pass around a rung  65  or ladder jack to prevent the plankform  10  from coming off its support structures. In  FIGS.  23  and  24   , a strap assembly  122  is connected to each of the legs of the first leg assembly  14  of the plankform  10 . As shown in  FIG.  27   , the strap assembly  122  comprises a base  124  with a strap  126  which can be flat web fabric or flat reinforced rubber material. The fixed end  128  of the strap  126  is connected to the base  124 . After passing around the step or ladder jack the free end  130  of the strap  126  is fed into and is held by a friction buckle  132  such as used on rifle slings, or a ratchet mechanism such as used on cargo tie down systems. See  FIGS.  29 - 32    of typical buckles and fastening systems. This arrangement enables the strap  126  to be cinched tight. 
       FIG.  25    shows a single strap  126  in which the strap assembly  122  is attached directly to the plank  12  portion of the plankform  10  instead of to the legs. The method of tightening the strap  126  is the same. The purpose is also the same with the intention of securing the plankform  10  to a ladder rung or ladder jack. 
       FIGS.  26  and  27    are more views showing the strap assemblies  122  on the legs and on the plank  12  surface as optional attachment locations. 
       FIG.  28    shows the end handle  133  design comprising a handle recess  136  for the user to put their hand in and grab onto the ergonomically designed end handle  133 . This helps the user to carry the plankform  10  and also helps the user to adjust the length of the plankform  10 . The end handle  133  fits into and aligns with the first end  16  and aligns with the top surface of the plank  12  so the end handle  133  defines a first flat plane with the first end  16  and a second flat plane with the top surface of the plank  12 . This way, the end handle  133  does not have portions which extend out and possibly cause the user to trip or catch on the end handle  133 . There is a recess  136  in the plank  12  adjacent the first end  16  aligned with the end handle  133  for the fingers of a hand to fit in to wrap around the end handle  133 . The recess  136  is about the same length as the length of the end handle  133 . Preferably, in this embodiment there is a handle bracket  134  which fits onto and is attached to the top surface of the first supports  54  adjacent to the first end  16 . The end handle  133  is disposed, as described above, in the handle bracket  134  and is centered in the handle bracket  134 , and has a length of about 1/3 the length of the handle bracket  134 . The handle recess  136  is disposed in the handle bracket  134 , as described above. The end handle  133  may have a square or rectangular cross-section. The handle bracket  134  may have tab stops  120  extending down from the handle bracket  134  to stop the first leg assembly  14  from extending open to far. The tab stops  120  also press against the first leg assembly  14  to tension the plankform  10  in the open position/work platform  10  mode. There may be a pinch lock  50  under the plank  12  and attached to the plank  12  to lock the first leg assembly  14  in the open position/work platform  10  mode or the closed position/plank  12  mode. The same description is applicable regarding a second end handle in regard to the second end  20 . 
     Although the invention has been described in detail in the foregoing embodiments for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be described by the following claims.