Step ladder device allowing the user to stand and work safely and comfortably on the upper steps of a step ladder
11578533 ยท 2023-02-14
Inventors
Cpc classification
E06C7/14
FIXED CONSTRUCTIONS
F16B7/105
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
E06C1/22
FIXED CONSTRUCTIONS
International classification
E06C1/22
FIXED CONSTRUCTIONS
F16B7/10
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A step ladder device for improving the safe working elevation of a step ladder is provided. The step ladder device includes a working ladder portion that terminates in a rigid working tray providing a safety grab bar. The step ladder device is dimensioned and adapted to piggyback on to the step ladder so that the working ladder portion slidably moves in a coplanar orientation relative to the underlying step ladder, which enables the working tray to be locked in one of a plurality of selective working elevations relative to the underlying step ladder. As a result, the user can embrace the safety grab bar and balance themselves while standing on the upper rungs of the underlying step ladder or the lower rungs afforded by the working ladder portion.
Claims
1. A step ladder system for improving a safe working elevation of a step ladder, comprising: a working ladder portion having an elongated frame extending between a proximal end and a distal end; a plurality of spaced apart cross rungs supported within the elongated frame; a working tray rigidly connected to the distal end; a grab bar fixed along an upper surface of the working tray; a cavity provided along a lower surface of the working tray; and a bumper provided along a front surface of the working tray.
2. The step ladder system for improving a safe working elevation of a step ladder of claim 1, further comprising: two rail extrusions dimensioned and adapted to attached along the step ladder and slidably receive the elongated frame.
3. The step ladder system for improving a safe working elevation of a step ladder of claim 2, further comprising: a plurality of frame lock holes in the elongated frame; and a lock tab located on each rail extrusion, each lock tab movable between an unlocked engagement and a locked engagement with one of the plurality of the frame lock holes preventing the elongated frame from moving downwardly but not upwardly.
4. A method of improving a safe working elevation of a step ladder, comprising: providing the step ladder having a front leg frame that terminates at a top rung; providing the step ladder system of claim 3; and attaching two rail extrusions to the front leg frame, one rail extrusion on each side thereof, wherein the elongated frame operatively associate with the two rail extrusions so that the working tray slidably moves in a parallel orientation relative to the front leg frame between a contracted position and one of a plurality of extended positions and wherein the top rung nests in the cavity in the contracted position.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE INVENTION
(10) The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
(11) Broadly, an embodiment of the present invention provides a step ladder device for improving the safe working elevation of a step ladder. The step ladder device includes a working ladder portion having in a working tray at a distal end. The working tray provides a rigidly connected safety grab bar. The step ladder device is dimensioned and adapted to piggyback on to the step ladder so that the working ladder portion slidably moves in a parallel orientation relative to the front legs of the underlying step ladder between a contracted position and a plurality of extended positions. The step ladder device also provides a locking element that, when combined with the slidable parallel movement, enables the working tray to have a selective working elevation relative to the underlying step ladder. As a result, while standing on the upper rungs of the underlying step ladder or the lower rungs afforded by the working ladder portion, the user can ergonomically utilize the working tray and embrace the safety grab bar.
(12) It should be understood by those skilled in the art that the use of directional terms such as upper, lower, upward, downwardly, top, left, right and the like are used in relation to the illustrative embodiments as they are depicted in the FIGS. The upward direction (or upper) being toward the top of the corresponding FIGS., the downward direction being toward the bottom of the corresponding FIGS., while the front and rear direction are in reference to the base step ladder 30, where the front direction faces a user climbing the climbing steps 34 of the base step ladder 30.
(13) Referring now to
(14) The base step ladder 30 provides front base legs 64 and rear base legs 44 movable relative to each other, scissor-like, between an open condition, illustrated in
(15) Referring to
(16) Rail extrusions 32 may be joined to the front base leg 64 of the base step ladder 30. The elongated frame 18 slides through openings 33 of the rail extrusions 32, the openings 33 being adjacent the top rung 36, to operatively associate with the front base legs 64 so as to slide in a parallel orientation relative thereto between the contracted position and the plurality of extended positions increasing the functional elevations attainable by a user.
(17) The rail extrusions 32 may also provide spaced apart rail lock holes 38 that align with the previously mentioned frame locking holes 22. At one or more rail lock holes 38 a lock bracket 40 may support a pivotable lock tab 42 that can move between a locked engagement and an unlocked engagement, as illustrated in
(18) The coplanar/parallel movement of the step ladder device 10 results in the fixed working tray 12 to be slidably raised to (and locked in) various extended positions in accordance with the user's desire for additional safety and working convenience. The working tray 12 elevation can be selectively controlled by the safety device 70, which may be unidirectional: adapted to prevent downward movement only, thereby enabling upward movement without the need to engage/unlock the safety device 70. Thus the use may merely push upward on the center of one of the rungs to increase the working elevation of the working tray 12 and grab bar 14, as opposed to having to reach for the periphery of the frame, which can cause the user to lose their balance or dangerously shift the center of gravity of the entire ladder system.
(19) The working tray 12 provides a rigidly joined grab bar 14 so that when a user is working at or near the top climbing step 34 of the base ladder portion 10 or on a cross rung 20 of the elongated frame 18, the grab bar 14 attach to the working tray 12 provides a brace point for maintaining the user's stability. The working tray 12 provides an underside cavity for receiving the top rung 36 of the underlying base step ladder 30 in a nested condition. The working tray 12 may provide a bumper 16 along a rear side thereof so that when the base step ladder 30 is in the closed condition, the combination of the base step ladder 30 and the piggybacked step ladder device 10 can lean against a vertical surface, in a traditional ladder configuration, with the bumper 16 engaging said vertical surface, as illustrated in
(20) A method of using the present invention may include the following. The step ladder device 10 disclosed above may be provided. Either the step ladder device 10 is integrated to the base step ladder 30 during initial construction or piggybacked on to a preexisting base step ladder 30 by attaching the rail extrusions 32 as mentioned above. A user may unfold the base legs 44 and 64 into the open condition and elevate the working tray 12 by pushing any cross rung 20 until a desired locked engagement forms by way of the lock tab 42. A user may selectively elevate the working tray 12 and its grab bar 14 while on a climbing step 34, simply by singe-handedly pushing up any of the cross rungs 20. In certain embodiments, for safety reasons no more than three cross rungs 20 may go up, while the fourth rung may be stopped by a safety device (not shown).
(21) To lower the working tray 12 the user must manipulate the lock tabs 42, typically located on the front of the rail extrusions 32, to move it to an unlocked engagement.
(22) The rail extrusions 32 can be manufacturing during the creation of the base step ladder 30 or be separate components that are fixed to the base step ladder portion 10 later. In order to be able to use a rail extrusion 32, the base step ladder 30 must be straight up and not angled as most step ladders are. In order to compensate for the loss of stability caused by the lack of angles, the base step ladder 30 may have extension feet 52 and 54, as illustrated herein. These extension feet are equal to the angles, providing stability.
(23) It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.