The present invention relates in general to ladder step attachment devices, and more particularly to an improved ladder step attachment device that can be mounted on a conventional extension ladder, providing additional foot support.
Ladder rungs are not sufficiently wide to provide a convenient and comfortable foot support for long periods of time. Painters, contractors, homeowners and others are frequently required to work for extended periods of time standing on the rungs. Ladder-mounted attachment devices aim to provide a platform to increase safety and comfort.
Several ladder step attachment devices are known in the art. For example, U.S. Pub. No. 2004/0163890 to Nash discloses a ladder step platform that can be mounted on any ladder having hollow rungs extending between ladder rails. The device includes a step platform extending between side plates that are positioned on the outside of the ladder rails. The space between the side plates can be adjusted to fit ladders of different width. A support rod, inserts through the hollow rungs, and pivotally supports the ladder step platform with the side plates. A lower adjustable rod abuts the ladder rails such that the step platform extends horizontally beyond the ladder. Unfortunately, the installation means of this device, for example the use of the support and adjustable rods, are inconvenient and difficult to use.
U.S. Pat. No. 5,052,515 to Nowlan discloses a ladder attachment comprising a platform, a vertical support member projecting from one edge of the platform, and two brackets. An upper bracket is intended to engage a rung of the ladder to impart lateral stability to the platform, while a lower bracket is intended to cooperate with a second rung of the ladder to provide lateral and vertical stability to the platform. The need for two rungs for support and the structure of this device, especially the vertical member and the two brackets, makes it bulky and difficult to operate with a single hand.
U.S. Pat. No. 1,820,315 to Miller discloses a ladder step attachment consisting of a step platform connected to a pair of transversely spaced metallic brackets and a transversely extending stop member. The metallic brackets have their upper ends formed to include hooks capable of being inserted over the rungs of the ladder. The horizontal feature of the metallic brackets are connected to the under surface of the step platform. Although the installation procedure appears to be similar, the hooks and the stop member of this device make it ineffective.
U.S. Pat. No. 6,786,300 to Bonifacini discloses a step unit that can be installed on the existing step of a conventional ladder. The unit comprises of a rectangular main body portion with one of its end bent downward and angularly outward with respect to the main body portion and terminates in a short upturned lip. The unit is installed by engaging the upturned lip against the bottom edge of the step and then pivoting the unit downwardly. The lip of the unit is then captured by the bottom edge of the step and the main body portion is supported on top of the step. However, the bent and upturned lip features of this device are different from the lip and the tubular members of the present invention.
Although these devices can be mounted on a ladder to provide additional foot support, they are frequently inconvenient to use, overly complex, or lack stability. Some devices Therefore, it is an object of the present invention is to provide an improved ladder step attachment device that is portable, simple and easy to install and uninstall, and strong enough to withstand the weight of a person. Other objects of the present invention will become better understood with reference to the appended summary, description, claims and illustrations.
This apparatus can be mounted on a ladder to provide a larger standing area for more comfortable foot support. Overall, the apparatus is characterized by a unitary, single-piece extruded aluminum construction, which lowers manufacturing costs, and avoids the need to assemble multiple parts with fasteners. The shape of the apparatus is characterized by a standing surface adapted to support a person, a lip member adapted to engage a ladder rung, and a support member adapted to brace against the ladder rails adjacent the rung. Tension created between the lip member engaged on the rung, and the support member engaged on the ladder rails holds the apparatus in position.
The standing surface is adapted to present a substantially horizontal standing surface to support a person when the apparatus is installed on a ladder. Preferably the upper surface comprises a non-slip feature for added traction. The standing surface is generally rectangular in top view except for notches designed to accommodate the ladder rails. The lip member is adapted to engage the back of the ladder rung and preferably comprises resilient stoppers, enhancing the ability of the lip member to engage the rung. In another embodiment, the lip member comprises horizontal ridges to keep it in position. The support member is characterized by a modified tube having a tube wall, a portion of which is shared with a portion of the standing surface, and another portion of which is adapted to abut a predetermined length of the ladder rails.
In order to mount the device on a conventional ladder, including an extension ladder, the lip member is brought to bear against a ladder rung, and the support member is disposed against the faces of the side rails of the ladder. With the lip member engaging the back of the rung, and the support member engaging the ladder rails, the standing surface is held in position at a substantially horizontal plane under tension, capable of supporting a person.
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The standing surface 12 comprises a non-slip feature. In one exemplary embodiment, the non-slip feature comprises ridges 22 on the standing surface 12 in parallel to a ladder rung. The ridges 22 facilitate gripping, while allowing any liquid falling on the standing surface 12 to drain off. In a preferred embodiment, the standing surface 12 is sized so that it projects outward beyond the plane of the ladder rails between 2 and 3 inches. It has been observed that this range presents the greatest standing area without presenting an obstacle when a user needs to climb around the ladder step attachment 10. In one embodiment the standing surface extends two and one half (2½) inches from the ladder rails.
The lip member 14 depends from the standing surface 12 in a manner designed to engage the rear of a ladder rung. In one exemplary embodiment, the lip member 14 depends at a seventy-five (75) degree angle from the standing surface 12. In another exemplary embodiment, the lip member 14 extends downward from the standing surface 12 approximately two (2) inches. In yet another exemplary embodiment, the lip member 14 comprises a gripping surface 24, designed to engage a ladder rung to prevent slippage.
Slippage of the lip member 14 is chiefly avoided by the use of at least one resilient stopper 26 disposed on the lip member 14. The resilient stopper 26, made of rubber in one exemplary embodiment, prevent the lip member 14 from moving vertically relative to a ladder rung by engaging the rung under pressure generated by a user's weight. As a user stands on the standing surface 12, downward pressure on the apparatus 10 urges the support member 16 down and away from the rung by virtue of the ladder's angle of lean. This causes the lip member 14 to tightly engage a ladder rung when a person stands on the standing surface 12.
The support member 16 is generally tube shaped. One portion of the support member 16 comprises a common wall 18 shared with the standing surface. Another portion of the support member 16 comprises a flat engaging portion 20, adapted to engage the rails of a ladder. The engaging portion 20, in one preferred embodiment is disposed at an angle twenty (20) degrees from vertical to match the angle of lean of a conventional ladder. With the engaging portion 20 abutting the rails of a ladder, the common wall 18 and the rest of the standing surface 12 are substantially horizontal.
Above the engaging portion 20 of the support member 16 is a non-engaging portion 28. A bend 30 separates the engaging portion 20 and non-engaging portion 28. The purpose of the non-engaging portion 28 and bend 30 is to facilitate removal of the ladder step attachment 10. Without the non-engaging portion 28 and bend 30, downward pressure on the ladder step attachment 10, combined with slight flexing, causes the ladder step attachment 10 to tightly engage a ladder as a person steps off the standing surface, preventing removal.
The remaining portions of the tubular wall of the support member 16, other than the common wall 18, engaging portion 20, and non-engaging portion 28 serve to connect those portions and form the modified tubular shape of the support member 16.
The apparatus having been shown and describe, its use will now be discussed.
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All features disclosed in this specification, including any accompanying claims, abstract, and drawings, may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features
Although preferred embodiments of the present invention have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.
This application is a continuation-in-part of application Ser. No. 11/375,872, filed on Mar. 14, 2006.
Number | Date | Country | |
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Parent | 11375872 | Mar 2006 | US |
Child | 12960367 | US |