Ladder leg shoe hinges 90 degrees and slides up

Abstract

Improvements to the leg extension of an adjustable ladder leveler and, more generally, improvements to ladder legs. A shoe with a claw that folds to be parallel to the ladder leg and then slides upward with respect to the leg thereby becoming locked into position so that it cannot move away from being parallel so long as weight is applied on the ladder. If the shoe is on an extension, as the shoe slides up, it engages a safety bar that prevents release of the extension.

Claims

1. A ladder leg extension comprising: an outer housing; a leg extension movable longitudinally in first and second directions relative to the outer housing between a retracted position and an extended position, the leg extension having an opening extending therethrough proximate a bottom of the leg extension; a bolt extending through the opening; and a shoe having an engagement base and first and second sidewalls extending upward form the engagement base, wherein each of the first and second sidewalls have an elongate hole through which the bolt extends to pivotally connect the shoe to the leg extension, wherein the first sidewall is triangular in shape with rounded corners a rounded top, and wherein the second sidewall has a horizontal portion extending upward from the engagement base and a vertical portion extending upward from the horizontal portion perpendicular to the horizontal portion thereby forming cutouts such that second sidewall is configured to avoid contacting a ladder rail or the outer housing when the leg extension is in the retracted position and when the shoe is moved from a first position where the engagement base is perpendicular to the leg extension to a second position where the shoe is fully hinged where the engagement base is parallel the leg extension, wherein each elongate hole is triangular in shape, and wherein each triangular shaped hole has a horizontal portion parallel the horizontal portion of the second side wall, and a pair of angled portions angled towards one another and extending downward from the horizontal portion.

2. The ladder extension according to claim 1, wherein when weight is applied to the leg extension when the shoe is in the first position, the bolt is configured to contact the horizontal portions of each triangular shaped hole.

3. The ladder extension according to claim 2, wherein when weight is applied to the leg extension when the shoe is in the second position, the shoe is retained in the second position.

4. The ladder extension according to claim 1, further including a friction pad tread attached to a bottom of the engagement base.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIGS. 1 and 2 show the prior art ladder leveler with an adjustable extendable leg.

(2) FIG. 3 shows the hole in the shoe for nailing.

(3) FIG. 4 shows two nails through the holes and through aligned holes in the rubber tread portion of the shoe.

(4) FIG. 5 shows the conical shaped raised metal around the hole to facilitate removing the nail.

(5) FIG. 6 shows the shoe with a triangular hole rotated 90 degrees but hanging low off the leg of the ladder.

(6) FIG. 7 shows the shoe still rotated 90 degrees but now pushed up from below so that the leg of the ladder extends lower than the triangular hole.

(7) FIG. 8 shows the lower foot pedal in a folded position and the upper release lever, each extending outward enough to be operable with a person's foot (shoe).

(8) FIG. 9 shows the lower foot pedal in the unfolded position for extending the leg.

DETAILED DESCRIPTION

(9) Ladder Shoe with Fastener Holes

(10) As shown in FIGS. 3 and 4, fastener holes 201 in the ladder shoe allow nails or screws or other fasteners to be inserted into dirt or wood or other material on which the ladder is erected to provide extra grip. Instead of holes, slots may be placed in the shoe. Most ladder shoes include a rubber tread 31 below a metal support structure 27. The tread may also have aligned holes so the nails can pass through both the metal structure and the rubber tread as shown in FIG. 4. These holes in both the metal and the rubber tread make the shoe lighter, which is always a design advantage for ladders. The holes are located near the ends of the shoe, large enough to slide a nail or similar, sharp or narrow, or thin metal or plastic piece through the hole or holes to penetrate a slippery surface, thereby providing additional non-slip features to the bottom surface of the shoe. The shoe will preferably include a claw on each end as shown in FIGS. 3 and 4, and the holes are near the claws.

(11) The hole or slot in the metal portion of the shoe can be the same size or slightly larger than the penetrating object, (i.e. 16d framing nail) to minimize any friction between the two objects, but the rubber tread underneath the metal portion can be slightly smaller than the penetrating object so that the rubber tread grips the penetrating object tightly, thereby minimizing the chance of it sliding back up and out too easily.

(12) The penetrating object may be slid into the hole or slot when a ladder or leveler is set up on a slippery surface, as an added safety measure. An example would be setting up a ladder on a mossy deck. A nail can be slid through the leveler shoe hole and in between the grooves in between deck boards. A 16d framing nail, or sinker, is the most common nail found on a construction site, used for general framing, temporary scaffolding, saw horses, etc. A 16d framing nail placed in a slightly larger hole in the metal, a slightly smaller hole in the tread make the best combination of holes and penetrating devices.

(13) Additionally, as shown in FIG. 5, the hole or holes in the shoe bottom can also have an upward protruding, semi-conical shape to allow easy removal of the nail. The smallest diameter portion of the semi-conical protrusion is located above the flat metal surface of the bottom portion of the shoe. This holds the head of the nail up and above the flat surface of the metal portion of the shoe, thereby enabling the claw of a hammer to grasp under the head of the nail to pull the nail more easily. A standard concrete form nail, with a double head, is another possible solution if a hole without the semi-conical shape is used in the shoe.

(14) The rubber tread 31 located under the bottom, metal surface of the leveler shoe, and riveted on, also has holes of a slightly smaller diameter, in line with the holes in the metal portion of the shoe, so that the nail can penetrate all the way though the shoe assembly, including the holes in rubber tread, and in between deck boards, or the nail can be pounded into a wood surface, such as a subfloor on a new building or on a sheathed roof (sloped or not) of a new structure. The nails can also be used to penetrate into a lawn or any other soft surface that may be wet, moldy, mossy and/or slippery. These holes can also be shaped as slots that would enable a shim or other sharp device to be slid through to act as a securing, or non-skid device.

(15) Claw Foot Locks in 90 Degree Rotation

(16) As shown in FIGS. 6 and 7, the shoe has been modified to enable it to pivot 90 degrees in one direction, or 90 degrees in the opposite direction, totaling a potential pivoting action of 180 degrees, without the need to extend leg extension when leg extension is fully retracted in the “ready” position and to slide up and down when pivoted 90 degrees. This feature enables the shoe to function as a claw that works in conjunction with the automatic, back-up safety mechanism of the leveler with extendable leg or with any ladder leg having a square bottom end of the leg.

(17) The shoe has specially designed shapes and sizes, with carefully designed relationships between the shapes and sizes, including an elongated hole 205 through which a hinge pin couples the shoe to the ladder leg. When used together, these shapes and sizes and holes enable the bottom tread/claw surface and assembly of the shoe to pivot into the parallel position, in relation to the leg, and then, once pivoted into a parallel position, upward force applied to a claw end of the shoe will slide the shoe upward, the elongated hole allowing the hinge pin to move downward in the hole as shown in FIG. 7, so that a lower corner of the square bottom of the ladder leg 206 contacts the shoe bottom structure to prevent the shoe from pivoting out of the parallel position. The contact surfaces which retrain the shoe in position are a bottom corner of the ladder leg 206 contacting the inside of the horizontal base plate of the shoe and a portion of the inner circumference of the elongated hole 205 contacting the hinge pin (which is bolt 33 in the preferred embodiment). The hole 205 is elongated in a direction parallel to the shoe base and may also be triangular as shown in FIGS. 6 and 7.

(18) In effect, the shoe becomes wrapped around the lower, outer leg, thus pointing the claw, on the desired end of the shoe, downward toward, and/or into the slippery surface on which the ladder is erected. These special shapes and dimensions allow the shoe to pivot and wrap around the bottom end of the lower leg, while working together with the automatic, back-up safety mechanism, and without any type of interference between the leveler leg, safety mechanism or shoe assembly. Both the shoe locking system and the release lever locking system will remain locked in their respective positions until weight is removed from the ladder leveler.

(19) These new features provide a ladder leveler with a shoe and an automatic, back-up safety lock, having metal claws on either one or both ends of shoe, with the ability to pivot 180 degrees, slide up and down the leveler leg assembly and remain locked parallel to the leveler leg, thereby enabling the claw to dig into ice, snow or other slippery surfaces without concern for accidentally tripping the shoe to the flat position while on the ladder and without concern for retracting the leg extension.

(20) There are various ways to achieve these results, including, but not limited to A.) specially designed, triangular shaped holes in two side flanges of leveler shoe as shown in FIGS. 6 and 7; B.) specially shaped and sized side flanges of the shoe; and C.) specially shaped and sized bottom support structure of the ladder shoe (attached to rubber tread). The shoe, with claw facing downward and penetrating or contacting a support surface, will not flatten out (down) when any weight or load is being applied to the ladder leveler, even if a load, sudden or otherwise, is applied from a direction that is different from the angle of the ladder leveler legs. The end result is that the claw shoe, automatic safety lock and primary ratchet lock all remain in the locked position as long as weight or load is applied to the ladder leveler leg or the ladder to which the leveler leg is attached, even if the load (sudden or gradual) is applied to the side, back, front or top of the ladder leveler or ladder to which the ladder leveler is attached.

(21) This invention provides much more versatility in the ladder leveler because it enables the ladder user to quickly and easily flip the leveler shoe all the way back or forward, allowing the inside, upper surface of the bottom portion of the shoe to slide up against the leg, thereby activating the automatic, back-up, safety mechanism up against the pawl (and its release lever), thereby keeping the pawl locked, without the need to extend the leg extension several inches beforehand. This option enables a ladder user, who prefers not to extend the leveler leg, to easily use the claw on either end of the shoe (double claw shoe—front and back) when setting up a ladder on flat, even surfaces, or uneven surfaces, with ladder levelers that have automatic, back-up safety mechanisms installed.

(22) Lever Controls Actuatable with a Person's Foot

(23) As shown in FIGS. 8 and 9, the release lever 75, which is the upper of the two levers, is modified in its length and its shape so that it protrudes at least ¼″, better ⅜″, preferably 9/16″, but not more than 1″, beyond the shoe-contactable boundary of the leveler, creating a preferred relationship between the outer surfaces of the leveler and outer portion of the release lever. Preferably, the tip of the lever 209 has a upward curve. This improvement enables the user to depress the lever with his or her foot, shoe or toe, more quickly, ergonomically and with less physical effort. The proximity and immediate relationship between the two parts (outer surface of the leveler and the release lever) is critically important in how the locking system will respond when touched with a foot, and also in relation to the automatic, back-up, safety mechanism, which is deactivated when weight (load) is removed from the leveler shoe.

(24) The increased length of the release lever adds significantly to the ease of operation by creating quick and easy access to the lever, even when a person with large feet (large shoes) is attempting to depress the lever to release the locking system and retract the leg extension. The slight upward bend 209 in the release lever, located approximately ¼″ from the outermost tip of the lever, creates an angled edge for shoes that may be slippery from being wet, muddy or smooth from wear that is much easier to snag with a foot or toe. Additionally, the top surface of the lever, including the upwardly curved tip 209, has grooves in it for extra grip. The release lever is also shaped so that it will not protrude from the outside face of the ladder leveler to a point at which it would be considered overly obtrusive, thereby creating interference, when the leveler is not in use and/or the ladder and leveler combination is being carried or stored.

(25) As shown in FIGS. 8 and 9, the foot pedal 101, which is the lower of the two levers, is modified in its length and its shape to enable the ladder user to quickly and easily catch the foot pedal of a ladder leveler with the bottom of a shoe or side of a shoe when the foot pedal needs to be snapped downward to the “READY” position for quickly extending the inner ladder leveler leg, thereby creating a faster, safer leveling operation without the need to bend over to use a hand to snap the foot pedal down into the “READY” position.

(26) The proximity and immediate relationship between the two parts (leveler's outer surface and the foot pedal) is critically important in how the foot pedal/locking system will respond when touched with a foot or shoe, particularly in relation to the automatic, back-up, safety mechanism, which is deactivated when weight (load) is removed from the leveler shoe, and activated when weight is placed on the leveler shoe. The special shape is designed so that it is easier to snap up and snap down with a foot, while activating or deactivating the back-up, automatic safety mechanism. This special shape, combined with the extra length (at least ⅛″ beyond the shoe-contactable boundary of the leveler, better 5/16″, preferably 9/16″, and no more than 1″ beyond the shoe-contactable boundary the leveler) is a more ergonomic shape, is easier to reach, and is combined with grooves running perpendicular to the length of the foot pedal for added non-slip features. The foot pedal is also shaped so that it will not protrude from the outside face of the ladder leveler to a point at which it would be considered overly obtrusive, thereby creating interference, when the leveler is not in use and/or the ladder and leveler combination is being carried or stored.