US2992696A

US2992696A - Anti-skid shoe for a ladder

Info

Publication number: US2992696A
Application number: US733094A
Authority: US
Inventors: Jedinak Michael
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-05-05
Filing date: 1958-05-05
Publication date: 1961-07-18
Anticipated expiration: 1978-07-18

Description

July 18, 1961 M. JJJJJ AK 2,992,696

' A TTOENE Y6 United States Patent 2,992,696 ANTI-SKID SHOE FOR A LADDER Michael Jedinak, 26240 Broadway, Bedford, Ohio Filed May 5, 1958, Ser. No. 733,094 2 Claims. (Cl. 182108) This invention relates to an anti-skid shoe especially designed for permanent attachment to the rail ends of a ladder, particularly a telescopic type of ladder construction.

It is an object of this invention to provide a new and improved anti-skid shoe especially designed for permanent attachment to the rail ends of the several sections of a telescopic type of ladder structure.

Another object of this invention is to provide a new and improved anti-skid shoe especially designed for permanent attachment to the rail ends of the several sections of a telescopic type of ladder construction and which is capable of presenting positive anti-skid action on a plurality of surface areas.

Still another object of the present invention is the provision of a new and improved anti-skid shoe especially designed for permanent attachment to the rail ends of the several sections of a telescopic type of ladder structure, and which permits the several sections to be used together and/or individually while affording antiskid action on the opposite extremities thereof.

Another object of this invention is to provide an antiskid shoe which is readily adaptable to a ladder construction having side rails of rectilinear cross section.

Additional objects and advantages will be realized to one skilled in the art to which it pertains upon reference to the following description of a preferred embodiment and as is illustrated in the accompanying drawings of which:

FIG. 1 is a view in perspective of a telescopic type of ladder having the anti-skid shoe of the present invention afiixed upon the top and bottom ends of the side rails thereof;

FIG. 2 is an exploded perspective view of an anti-skid shoe embodying the present invention, and which is shown adjacent a rail end of a ladder structure and in a position to be moved toward the same for permanent attachment thereon; and

FIG. 3 is a fragmentary view in perspective of a ladder structure showing one rail end thereof with an antiskid shoe of the present invention permanently attached thereto.

As may be seen in the drawings, particularly in FIG. 1, a ladder of the telescopic type, as referred to in the art, is designated generally by the reference numeral '10, and in its present form consists of two separate sections 11 and 12 which have their upper and lower ends, respectively, interconnected one with the other such that the same are in substantial longitudinal prolongation in a well known manner. Each of said sections comprises a pair of

elongated rails

13 and 14, preferably of rectangular cross section, which are disposed in predetermined spaced relation and have a plurality of rungs 16- interspaced and anchored therebetween as is well understood.

The anti-skid shoe of the present invention, the instant form being identified by the reference character 17, is shown to be permanently attached to the rail ends of the several sections by means of suitable fasteners 18, and is of such new and improved construction (as will be hereinafter apparent) as to enable the ladder to be placed in a normal operative position while at the same time affording anti-skid support on each of its opposed ends. Specifically, as is seen in FIG. 1, the shoes on the bottommost rail ends on the ladder section 11 engage with the V-shaped valley 25, therebetween.

2,992,696 Patented July 18, 1961 supporting floor A whereas, those on the uppermost rail ends of ladder section 12 likewise engage with the surface of the wall section W. In this manner, said shoes prevent the ladder from slipping over either supporting surface, while at the same time, also preventing the hard material of said ladder from coming into direct contact with said surfaces and hence, prevent the marring or scratching of the same.

Referring now particularly to FIGS. 2 and 3., the antiskid shoe of the present invention, as herein shown, comprises a flat rectangular plate 20 constructed of a metallic material of a suitable thickness and having a pair of right angle brackets or flanges 21 being formed integral therewith and struck upwardly from adjoining edges on one end of the same. As is seen .in FIG. 2, one leg of each of said flanges lies along one of the longitudinal edges of said plate, whereas, the remaining leg lies along the adjacent transverse edge, the said legs being integrally connected by a curved radius portion interposed therebetween in such manner as to present a continuous external surface, as indicated at 22.

The brackets or flanges 21 each have a pad or boot 23 suitably bonded to the aforesaid surface 22 of the same, and as is herein shown, said pad is preferably constructed of a suitable pliable material such as rubber which has a relatively high coefficient of friction and which is formed to have the general configuration of said flange. Specifically, with reference now directed to FIG. 2, each of said pads is formed with a central curved part 23a, the latter having a thickened medial portion defining an external surface somewhat parabolic in form and which tapers downwardly on either end thereof to integrally connect with a pair of leg parts 23b, each of which projects outwardly therefrom in substantial perpendicular relation and has a smooth tapering surface as indicated at 230. The aforesaid central curved part 23a of said pad is of such radius as to closely fit around the curved portion of the flange 21 whereas the leg parts 23b are likewise adapted to closely lie against the leg portions of the same.

Said pad is also seen to have a series of raised teeth 24 which extend substantially transversely across the same in preselected parallel spaced relation, and which are disposed longitudinally therealong in said manner that each of the opposed end teeth of said series is in juxtaposition to the aforesaid surface 23c of the associated leg part 23b adjacent thereto. Each of said teeth, in addition, is preferably of triangular configuration having diverging side walls 24a and 24b, respectively, the adjoining walls of any one pair of teeth thereby defining a Said teeth are also intended to project outwardly of the pad such that an imaginary line connecting the aforesaid smooth surface portions 230 and the apex of each of said teeth is substantially parabolic in configuration, the purpose for which will be hereinafter apparent.

In plate 20 of the ladder shoe "17 of the present invention there is also provided a slot, designated by the reference numeral 26, which extends longitudinally partially through the center of the same, being closed at the inner end thereof by a radius portion 26a, and opening at the opposite end between the aforesaid flanges 21. Said slot is of such dimension as to slidably accommodate a rung 16 of the ladder construction whereas the aforesaid radius is such as to closely embrace the peripheral surface of the same.

As previously mentioned, the anti skid shoe of the present invention is permanently attached to the present instance to the rail ends of the ladder sections 11 and 12 and to accomplish this each of the lateral surface parts of said ends is curved, as is indicated at 27, in such J) manner as to closely fit the inner surface 28 of the shoe flange 21. Said rail end is also centrally formedwith a rung slot 29 adapted to accommodate the endmost rung of the next adjacent ladder section as is well understood.

The ladder shoe is permanently attached by suitable fastening means, as is previously described, to each of the rail ends of the ladder sections, in the manner as is shown in FIG. 3, such that the rubber pads or boots 23 extend around the aforesaid lateral surface parts of the same, and the aforesaid rung slot in the shoe plate and associated rail end are in substantial alignment. With the telescopic type of ladder structure herein shown, the shoes on the upper ends of the

rails

13 and 14 are preferably mounted in place with the plate 20 against the inside surface 30 of the said rails.

With the ladder shoe thus mounted, it will now be realized that with the several ladder sections 11 and 12 attached to each other, :as is seen in FIG. 1, and with the ladder structure thus propped against the 'Wall W, the rubber pads 23 on one side of each of said shoes, attached to the bottom rail ends of the lowermost ladder section 11, frictionally engage with the floor A, and thus prevent the same from sliding over the surface of the same. In like manner, the rubber pads 23 on one side of each of said shoes, attached to the top rail ends of the upper ladder section 12, frictionally engage with the surface of the aforesaid wall W, and hence also prevent the said upper end of the ladder structure from sliding over said surface. An important feature of the present construction of rubber pad relates to the manner in which the exterior surface thereof is disposed so as to subscribe a parabolic curve, as above defined. Speci' fically, as will be understood in the art, the ladder structure is normally propped against the wall W at a suitable acute angle such that the distance between the lowermost rail ends of the ladder section 11 supported by the floor A and the edge of the latter defined by the adjoining wall W, is substantially less than the distance between said floor edge and the top rail ends of the ladder section 12 supported by said wall. As a result of this normal positioning of the ladder structure, the ladder shoes of the present invention are hence capable of presenting a substantially large surface area to the supporting floor and wall and thereby provide for greater anti skid action than would otherwise be possible, for instance, if the same were constructed having a circular exterior configuration.

As is therefore now realized, the ladder structure may be selectively positioned at a plurality of angular projections and the instant ladder shoes will efiect a maximum anti skid action by being capable of presenting various surface parts of the rubber pads for direct engagement with the supporting floor and wall.

It will also be realized that with the rubber pads 23 on the ladder shoe extending over and beyond the lateral edge of the several rail ends, the hard ladder material is prevented from coming into contact with the aforesaid Wall and floor and hence prevented from marring or scratching the same.

It will be further realized that with the instant ladder shoe attached to the rail ends of the ladder structure in the manner as above described, said structure may be placed upon the floor, for instance while it'is not being used, and the lateral projecting parts of the rubber pads are effective to space said ladder structure slightly above said floor and hence also prevent the same from marring the surface of the said floor. It is also realized that the instant form of ladder shoe prevents the rail ends from splitting, as is common of the ladders in present use, since the rubber pads take up or absorb any shock presented thereto for instance, as a result of the ladder being dropped on either of its ends.

Having thus described in detail, one preferred embodiment of ladder shoe of the present invention it will be realized that the same is susceptible to various modifications and arrangements of parts without departing from the inventive concepts as are herein disclosed.

What is claimed is:

1. An anti-skid ladder shoe for permanent attachment to the rail ends of a ladder of the class described, comprising a fiat metal plate and means for mounting said plate to the side surface of a ladder rail adjacent either of its ends, a pair of right angle flange members formed integrally on one end of said plate projecting substantially perpendicularly outwardly therefrom to extend around and embrace the opposed adjoining longitudinal and transverse edge portions of said rail end, and a continuous pad of rubber-like material bonded to the surface of each of said flange members remote from said edge portions and having a curved surface substantially parabolic in configuration and positioned to frictionally engage a supporting surface for said rail end to prevent slippage of said ladder.

2. An anti-skid ladder shoe as defined in claim 1, and wherein said flat plate is formed with a slot extending centrally longitudinally partially therethrough being interspaced and opening between said flange members, said slot being formed to align with a rung slot in said rail end to thus accommodate a ladder rung.

References Cited in the file of this patent UNITED STATES PATENTS 178,480 Spaulding June 6 1876 375,249 Bacon Dec. 20, 1887 2,372,003 Kennedy Mar. 20, 1945 2,423,659 Rabe July 8, 1947 2,567,989 Check Sept. 18, 1951 FOREIGN PATENTS 1,821 Great Britain of 1899 4,106 Great Britain of 1899