CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The priority of U.S. Provisional Application No. 62/776,597, filed December 7, 2018 is hereby claimed and the specifications thereof are incorporated herein by reference.

FIELD OF THE DISCLOSURE

[0002] The following disclosure generally relates to apparatus and methods for providing a temporary work surface on a tank shell ladder. More particularly, the following disclosure relates to a lightweight work surface which may be affixed to a tank shell ladder to provide a work surface on which to stand while also able to be readily moved out of the way for ascent or descent on the ladder.

BACKGROUND

[0003] Storage tanks typically have pre-existing ladders permanently affixed to permit ascent and descent. These ladders, however, lack work surfaces, particularly a surface on which someone may stand without maintaining a hand on the ladder. Additionally, permanent installation of a work surface creates additional liabilities as third persons may trespass or as the work surface may weaken over time, such as by corrosion. Moreover, the work surface must not interfere with the operation of the ladder, namely ascent and descent.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The detailed description is described with reference to the accompanying drawings, in which like elements are referenced with like reference numbers, and in which:

[0005] FIG. 1 is an illustration of an isometric view of the platform of the present disclosure attached to a tank shell ladder in the first, deployed position. [0006] FIG. 2 is an illustration of an isometric view of the platform of the present disclosure attached to a tank shell ladder in the second, stowed position.

[0007] FIG. 3 is an illustration of an exploded isometric view of the platform of the present disclosure illustrating the platform of the present disclosure.

[0008] FIG. 4 is an illustration of a top view of the main body of the platform of the present disclosure prior to bending into shape.

[0009] FIG. 5 is an illustration of a bottom view of an embodiment of the first siderail clamp.

[0010] FIG. 6 is an illustration of an interior view of an embodiment of the first siderail clamp.

[0011] FIG. 7 is an illustration of a side view of an embodiment of the first siderail clamp prior to the material being bent to shape.

[0012] FIG. 8 is illustration of a side view of an embodiment of the first siderail clamp after the material has been bent to shape.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

[0013] The subject matter disclosed herein is described with specificity, however, the description itself is not intended to limit the scope of the disclosure. The subject matter thus, might also be embodied in other ways, to include different structures, steps and/or combinations similar to and/or fewer than those described herein, in conjunction with other present or future technologies. Although the term“step” may be used herein to describe different elements of methods employed, the term should not be interpreted as implying any particular order among or between various steps herein disclosed unless otherwise expressly limited by the description to a particular order. Other features and advantages of the disclosed embodiments will thus, be or become apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such features and advantages be included within the scope of the disclosed embodiments. Further, the illustrated figures are only exemplary and are not intended to assert or imply any limitation with regard to the environment, architecture, design, or process in which different embodiments may be implemented. The embodiments disclosed herein thus, may be used to in connection with any ladders, particularly those positioned vertically, such as those associated with tanks for storing cryogenic liquids.

[0014] The apparatus and methods disclosed herein overcome one or more of the prior art disadvantages of use of a ladder as a worksurface. The apparatus of the present disclosure can be easily installed and provides an adjustable removable platform which is readily moved to permit use of the ladder. The platform of the present disclosure can be constructed to be lightweight, resistant to be corrosion, and to include a non-slip surface.

[0015] In one embodiment, a platform for use on a ladder having a first siderail, a second siderail, and a plurality of rungs is disclosed, the platform comprising: i) a first siderail clamp; ii) a rung hook; iii) the rung hook having a rung hook first leg; iv) the rung hook having a rung hook second leg; v) the rung hook having a rung hook connector from the rung hook first leg to the rung hook second leg; vi) the rung hook having a rung hook passage therethrough at the rung hook first leg second end; vii) a pivot pin, the pivot pin positioned through a first siderail clamp mounting passage and attached to the rung hook first leg at the rung hook passage; and viii) a deck attached to the rung hook at the rung hook connector.

[0016] Referring to FIG. 1, an illustration of the platform of the present disclosure in a first, deployed position, is provided. The platform 100 is provided for use on a ladder 102 having a first siderail 104, a second siderail 108, and having a plurality of a rungs 112. The platform 100 temporarily locks onto a rung 112 while pivotally and slidably locking on the first siderail 104 and the second siderail 108 and thus provides a stable worksurface. The first siderail 104 may have a first siderail depth 110. Each of the plurality of rungs 112 may be separated from the adjacent rung 112 by a rung gap 120 and each rung 112 may have a rung depth 114 and a rung height 116. Preferably, the deck distance from the deck working end 384 to the rung hook passage 360 is less than the rung gap 120 so that the deck 364 may rotate from the first, deployed position illustrated in FIG. 1 to the second, stowed, position illustrated in FIG. 2.

[0017] Referring to FIG. 2, an illustration of the platform of the present disclosure in a second, stowed, position is provided. The platform 100 is disengaged from the rung 112 and permitted to pivot relative to the first siderail 104 and the second siderail 108 until resting in a stowed position intermediate the ladder 102 and the associated tank 118. Workers can thus ascend and descent the ladder 102 without interference from the platform 100.

[0018] Referring to FIG. 3, an illustration of an exploded isometric view of an embodiment of the platform of the present disclosure is provided. The platform 100 includes a first siderail clamp 340, a rung hook 320, a pivot pin 362, and a deck 364. The cooperation of these components permits the platform 100 to be locked into the first, deployed position and moved to the second, stowed, position. The rung hook 320 has a rung hook first leg 322, a rung hook second leg 324, and a rung hook connector 326 from the rung hook first leg 322 to the rung hook second leg 324. The rung hook 320 has a rung hook passage 360 therethrough at a rung hook second leg second end 338. The pivot pin 362 is positioned through a first siderail clamp mounting passage 354 and attached to the rung hook first leg 322 at the rung hook passage 360. The pivot pin 362 may be affixed to the rung hook second leg 322 or connected to a nut 363 which permits the loosening or tightening of the first siderail clamp 340 relative to the rung hook second leg 324. The deck 364 is attached to the rung hook 320 at the rung hook connector 326. The rung hook connector 326 may include an narrowing, angular profile 372.

[0019] The rung hook first leg 322 may have a rung hook first leg height 332 measured from a rung hook first leg first end 336 to a rung hook first leg second end 337. The rung hook second leg 324 may further have a rung hook second leg height 328. Because the rung hook 320 permits capture and release of a rung 112, the rung hook second leg height 328 may be selected to be greater than the rung hook first leg height 332.

[0020] The first siderail clamp 340 may have a first siderail clamp c-channel body 344 and a first siderail clamp mounting tab 352. The first siderail clamp c-channel body 344 may have a first siderail clamp c-channel body depth 346 measured from a first siderail clamp c- channel body rear 348 to a first siderail clamp c-channel body front 350 which is greater than the first siderail depth 110. The first siderail clamp mounting tab 352 may be attached to the first siderail clamp c-channel body 344 at the first siderail clamp c-channel body front 350 and having a first siderail clamp mounting passage 354 therethrough.

[0021] In use, the platform 100 is positioned between two ladder rungs 112 and between the first siderail 104 and the second siderail 108. The first siderail clamp 340 is positioned external the first siderail 104 and brought into contact with the rung hook 320 by tightening the pivot pin 362, until the first siderail 104 is captured, rendering the platform slidably connected to the ladder 102. The platform 100 is rotated sufficient for the foot 334, when present, and the rung hook 320 to pass by each ladder rung 112 without interference, and slid upward on the ladder 102 so the rung hook 320 can be raised above and lowered onto a ladder rung 112, capturing the ladder rung 112 in the rung hook connector 326 and between the rung hook first leg 322 and the rung hook second leg 324, providing the platform 100 in the first, deployed position illustrated in FIG. 1. When desired to move to the second, stowed, position illustrated in FIG. 2, the platform 100 is moved upward on the ladder 102 until the rung hook 320, and particularly the rung hook first leg 322, is clear of the ladder rung 112, and is then pivoted about the pivot pin 362 so the platform 100 rotates to the opposite side of the ladder 102.

[0022] Referring to FIGS. 3 and 4, the platform 100 may include a second siderail clamp. Because the second siderail 108 has a second siderail depth 106, the platform 100 may include a second siderail clamp 302 and a second rung hook 492. The second rung hook 492 includes a second rung hook first leg 420, a second rung hook second leg 462, a second rung hook second passage 460 therethrough at a second rung hook second leg second end 490, a second rung hook connector 494 from the second rung hook first leg 420 to the second rung hook second leg 462 and a second foot 434. The second rung hook connector 494 may include a narrowing angular profile 496. As with the first siderail clamp 340, the second siderail clamp 302 includes a second pivot pin 366 positioned through a second siderail clamp mounting passage 314 and attached to the second rung hook second leg 462 at the rung hook second passage 460. When the platform 100 is placed to the inside of the ladder 102 on which it has been installed allows the personnel to access the rungs 112 and continue climbing the ladder 102 to their desired location.

[0023] The second siderail clamp 302 may have a second siderail clamp c-channel body 304 and a second siderail clamp mounting tab 312. The second siderail clamp c-channel body 304 may have a second siderail clamp c-channel body depth 306 measured from a second siderail clamp c-channel body rear 308 to a second siderail clamp c-channel body front 310 greater than a second siderail depth 106. The second siderail clamp mounting tab 312 may be attached to the second siderail clamp c-channel body 304 at the second siderail clamp c-channel body front 310 and may have a second siderail clamp mounting passage 314 therethrough.

[0024] Referring again to FIGS. 3 and 4, the platform 100 may be strengthened by a strut from the deck 364 to a nearby rung hook second leg second end 338. When a second siderail claim 302 is used, a second strut may also be employed. When employed, a strut 368 may extend from a deck working end 384 of the deck 364 to a rung hook second leg second end 338 at the deck second end 486. With respect to the first siderail clamp 340, the strut 368 may be a standalone bar or may be incorporated into a first wall 370. Similarly, a second strut 468 may extend from the deck working end 384 of the deck 364 to the second rung hook second leg second end 490.

[0025] To aid in the capture of the first siderail 104, the platform 100 may further include a foot 334 at the rung hook second leg second end 338 extending away from the strut 368 and aligned at its base 335 with the rung hook passage 360. The foot 334 may be provided for resting on a ladder rung 112 and thereby provide a connection to the ladder 102 and a surface for transfer of load from the platform 100 to the ladder 102. The foot 334 may further provide a surface to further capture the first siderail 104 and to cause the platform 100, when moved downward, to rotate sufficient for the rung hook 320 to be clear of each ladder rung 112. The strut 368 and the rung hook 320 may be integrated into a first wall 370. Similarly, the second strut 462 and the second rung hook 492 may be integrated into a second wall 470. To further strengthen the deck 364 of the platform 100, a deck first stiffener 482 may be provided at the deck working end 384, a deck second stiffener 484 may be provided at a deck second end 486, a strut stiffener 488 may be provided at the strut 368.

[0026] Referring to FIG. 4, the platform 100 may be constructed with a minimum of welds, which are prone to crack propagation, and instead with a series of bends to metal, providing strengthening. The deck 364 may be constructed from the same single sheet as the deck first stiffener 482 and the deck second stiffener 484, the rung hook 320, the second rung hook 492, the foot 334, the second foot 434, the strut 368, the second strut 462, the strut stiffener 488, the second strut stiffener 472, the first wall 370, the second wall 470 may be provided for increased strength and performance.

[0027] Referring to FIG. 5, an illustration of a bottom view of an embodiment of the first siderail clamp 340 is provided. Preferably, the first siderail clamp 340 is constructed of a single plate, bent to shape, to avoid welds. The first siderail clamp c-channel body 344 thus has the first siderail clamp c-channel body depth 346, the first siderail clamp c-channel body rear 348, the first siderail clamp c-channel body front 350, the first siderail clamp mounting tab 352 having a first siderail clamp mounting passage 354 therethrough. The first siderail clamp c-channel body 344 is composed of a first c-channel panel 502, a second c-channel panel 504, and a third channel panel 506.

[0028] Referring to FIG. 6, an illustration of an interior view of an embodiment of the first siderail clamp 340 is provided and includes the first siderail clamp c-channel body 344 and the first siderail clamp mounting tab 352.

[0029] Referring to FIG. 7, an illustration of a side view of an embodiment of the first siderail clamp 340 prior to the material being bent to shape is provided. Welds are avoided. The first siderail clamp 340 includes the first siderail clamp c-channel body rear 348, the first siderail clamp c-channel body 344, the first siderail clamp c-channel body front 350, and the first siderail clamp mounting tab 352 having a first siderail clamp mounting passage 354 therethrough.

[0030] Referring to FIG. 8, an illustration of a side view of an embodiment of the first siderail clamp 340 after the material has been bent to shape is provided. Welds are avoided. The first siderail clamp 340 includes the first siderail clamp c-channel body rear 348, the first siderail clamp c-channel body 344, the first siderail clamp c-channel body front 350, and the first siderail clamp mounting tab 352 having a first siderail clamp mounting passage 354 therethrough. The first siderail clamp c-channel body 344 is formed by bending the first c-channel panel 502 at a right angle in relation to the a second c-channel panel 504 and by pending the third channel panel 506 at an opposite right angle in relation to the a second c-channel panel 504.

[0031] In operation, the platform 100 easily slides up and down the first siderail 104 and the second siderail 108 for easy adjustment to the ladder rungs 112. Once fastened on to the ladder rung 112 the deck 364 is a solid platform to stand on to perform work. The platform 100 can be easily reverted to allow full access to the front side of the ladder 102 for climbing up or down on the rungs 112 of the ladder 102. Beneficially, the platform 100 allows a worker to stand on solid platform which provides more comfort than working from a single ladder rung 112

[0032] To promote safety, the platform 100 may be constructed of aluminum to avoid corrosion and may include a perforated deck 364 to provide a non-slip surface. As a result, the platform 100 may be constructed to have a total weight of approximately 4 lbs and be rated for 300 lbs load. A lightweight, all aluminum construction with bolts as the pivot pin 362 with a nut 363, such as a lock nuts, is thereby provided to adhere to the first siderail 104 and the second siderail 108 which allow sliding of the platform 100 up and down the first siderail 104 and the second siderail 108 so that the platform 100 may be positioned around a ladder rung 112.

[0033] The platform 100 therefore aids in working from a vertical tank shell ladder to aid in erecting, fitting, welding, and inspection of above-ground steel storage tanks. The platform reduces the human exposure to standing on 0.75 inch diameter or square bar steel ladder rungs 112 when working from a ladder 102 while performing any of these tasks. The platform 100 allows a worker to safely and comfortably access areas on the tank shell to perform the daily duties required when erecting tank shell sections. The platform 100 thus reduces worker fatigue and provides a better way when accessing the shell from a vertical steel shell ladder 102 and not stand on the narrow rung 112 of the ladder 102 to perform required tasks. The deck 362 provides a lightweight non-slip platform and reduces the fatigue factor experienced by welders, fitters and inspectors when performing tasks from ladders with improved workplace ergonomics.

[0034] Moreover, the platform 100 provides a cost savings by reducing the number of shell equipment for repetitive tank building tasks and maximizing the total amount of work performed using the platform 100 The platform further provides an increase in efficiency and productivity by reducing inspection lag time and eliminating the need for a crane to place a ladder to aid in ladder and ease of use. The platform 100 further aids in weight reduction and reduction of human exposure to hazards normally experienced when standing for long periods on a small ladder rung.

[0035] While the present disclosure has been described in connection with presently preferred embodiments, it will be understood by those skilled in the art that it is not intended to limit the disclosure to those embodiments. It is therefore, contemplated that various alternative embodiments and modifications may be made to the disclosed embodiments without departing from the spirit and scope of the disclosure defined by the appended claims and equivalents thereof.