SELF LEVELING STEPLADDER WITH A UNIVERSAL HINGE JOINT

Abstract

A self leveling stepladder with a universal hinge joint providing many new advantages that traditional a-frame step ladders are not capable to offer.

Claims

1. A self-leveling ladder apparatus comprising: a first ladder frame having a first side and a second side, a second ladder frame having a first side and a second side, and a single universal hinge joint coupled to the first ladder frame and the second ladder frame, the universal hinge joint being configured to allow the first ladder frame to pivot about a plurality of axes relative to the second ladder frame, wherein the first ladder frame has a first leg and a second leg, the first leg having a length that is substantially similar to a length of the second leg, and a plurality of parallel rungs supported between the first and second leg of the first ladder frame, and each leg having a base for providing contact with a ground surface, wherein the second ladder frame has a first leg and a second leg, the first leg having a length that is substantially similar to a length of the second leg, and a plurality of parallel rungs supported between the first and second leg of the second ladder frame, and each leg having a base for providing contact with a ground surface, and said plurality of parallel rungs of said first ladder frame having an upper most rung and said plurality of parallel rungs of said second ladder frame having an upper most rung, wherein said single universal hinge joint is configured and adapted with connecting means joining interior sides of the upper most rung of said first ladder frame and upper most rung of said second ladder frame and forming a pivoting axis such that the first ladder frame and second ladder frame pivot about and thereby allowing the first side of the first ladder frame to pivot and move apart relative to the first side of the second ladder frame as the second side of the second ladder frame pivot and move apart to allow the first ladder frame to increase or decrease an angle relative to the second ladder frame and said ladder frames to move relative to one another along a plurality of axes such that each of the legs may rest on the ground at different heights relative to one another allowing all legs stability on uneven ground.

2. The self-leveling ladder apparatus of claim 1 wherein said first ladder frame and the second ladder frame move about said pivoting point in more than one axis relative to one another about both the longitudinal and lateral axes simultaneously.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Embodiments of the present disclosure are described herein with reference to the drawings, in which:

[0009] FIG. 1 is a side front perspective drawing image of the self-leveling step ladder self-leveling on uneven ground, in accordance with an embodiment of the instant invention;

[0010] FIG. 2 is a side rear perspective drawing image of the self-leveling step ladder self-leveling on uneven ground, in accordance with an embodiment of the instant invention;

[0011] FIG. 3 is a front perspective drawing image of the self-leveling step ladder self-leveling on uneven ground, in accordance with an embodiment of the instant invention;

[0012] FIG. 4 is an exploded top perspective image of the hinge comprised of a rubber tendon joint as the universal hinge, in accordance with one embodiment of the instant invention;

[0013] FIG. 5 is an exploded top perspective image of the hinge comprised of a ball and socket joint as the universal hinge, in accordance with another embodiment of the instant invention;

[0014] FIG. 6 is an exploded top perspective image of the hinge comprised of a mechanical joint as the universal hinge, in accordance with another embodiment of the instant invention;

[0015] FIG. 7 is an exploded top perspective image of the hinge comprised of a set of interlocking eye joints serving as the universal hinge, in accordance with another embodiment of the instant invention; and

[0016] FIGS. 8A and 8B are side and top views of the hinge comprised of a rope threaded ball joint as the universal hinge, in accordance with another embodiment of the instant invention.

[0017] FIG. 9 is an alternate embodiment illustrating a Y-shaped frame side, in accordance with another embodiment of the invention.

[0018] The novel features which are characteristic of the invention, as to organization and method of use, together with further objects and advantages thereof, may be better understood from the following brief disclosure considered in connection with the accompanying drawings in which one or more preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention.

DETAILED DESCRIPTION

[0019] The novelty of this invention revolves around the movement allowed by an unconventional hinge. Its unique design can be applied to almost any type of fold out step ladder. By virtue of the hinge, the two sides of a fold-out step ladder are allowed full movement in all planes. The two sides can open conventionally and also swing from side to side and at angles to each other. Their movement allows all four legs of the ladder to find contact with uneven ground and provide a stable platform to climb up on.

[0020] The universal hinge may be many possible versions, as illustrated in FIGS. 4-8. For example, the universal joint may comprise an embodiments as simple as two linked eyes (FIG. 7), one on each step frame, a piece of rope or cable passing through each frame. Or, alternatively, in another embodiment, a more complex version such as a knuckle style joint (FIG. 5), similar to that used in automobile suspension. Whatever way, free movement to both frames will allow for all four legs to be stable on uneven ground.

[0021] Although this is a novel universal joint, there is nothing highly technological about the hinge. It could be merely two eye bolts linked together or two U-bolts; one attached to either frame. It could be as simple as a cable or tendon (FIG. 6) from one side to the other. This design allows the ladder to open conventionally and also allows the frames to move from side to side independent of each other. It is this free movement in all planes that allows for all four legs to contact the uneven ground at the same time. The ladder very easily and quickly finds a stable position for safe climbing.

[0022] The applications and usage are many for the instant invention, ranging from a two or three step utility ladder, to high reaching ladders suitable for fruit picking. The invention will suit any application using a four-legged adjustable ladder on uneven ground. This style of four legged fruit picker ladder is much more stable than the three legged version. All versions allow movement in three planes to allow four-leg contact and engagement with uneven ground. It is to be appreciated that one or more of the elements depicted in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. Thus, while the present invention has been described herein with reference to particular embodiments thereof, a latitude of modification, various changes and substitutions are intended in the foregoing disclosures, and it will be appreciated that in some instances some features of embodiments of the invention will be employed without a corresponding use of other features without departing from the scope and spirit of the invention as set forth.

[0023] For example, the ladder having a wider base going up to a more triangular pointpicker style—could be made of aluminum and fiberglass sides and round ladder rungs. Various sizes will accommodate all sorts of picking from straddling berries to picking coffee, for example, on mountain sides and all kinds or other fruits up to 16 feet or more. In other examples, configuring the instant invention as a low level two or three step ladder—non wobbly—for garden use, clipping and pruning.

[0024] Therefore, many modifications may be made to adapt a particular situation or material to the essential scope and spirit of the present invention. It is intended that the invention not be limited to the particular terms used and/or to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include any and all embodiments and equivalents falling within the scope of the instant disclosure.

[0025] The foregoing description of illustrated embodiments of the present invention, including what is described herein, is not intended to be exhaustive or to limit the invention to the precise forms disclosed herein. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the present invention, as those skilled in the relevant art will recognize and appreciate. As indicated, these modifications may be made to the present invention in light of the foregoing description of illustrated embodiments of the present invention and are to be included within the spirit and scope of the present invention.