US2147052A

US2147052A - Ladder foot extension

Info

Publication number: US2147052A
Application number: US113141A
Authority: US
Inventors: Noone Frank
Original assignee: Individual
Current assignee: Individual
Priority date: 1936-11-28
Filing date: 1936-11-28
Publication date: 1939-02-14
Anticipated expiration: 1956-02-14

Description

Feb. 14, 1939.

F. NOONE LADDER FOOT EXTENSION Filed Nov. 28, 1936 INVENTOR flag? JYoone p Patented eb. 14,- 1939 UNITED STATES PATENT OFFICE moan FOOT nxmnsron I Frank Noone, Seattle, Wash. Application November as, 1936, Serial No. 113,141

2 Claims. (c1. 22a -s1) This invention relates to a ladder foot extension and the primary object of this invention is to provide adjustable extension means for the lower end portions of the side rails of a. ladder to compensate for slope or inclination or other unevenness of the surface on which the lower end portion of. the ladder rests when the ladder is in a generally upright position such as it will occupy when in use.

In the use of a ladder it frequently happens that the ground or the sidewalk or some other support on which it is necessary to place the foot of above the support. In such a position the ladder is not firmly and safely supported but is unstableand liable to tip to one side. If blocking is placed under the bottom end portion of the elevated 25 side rail the blocking is liable to slide or roll and the ladder is liable to be unsafe and accidents are liable to result. Also when a ladder is supported entirely or principally on one side rail the presence of a load on the ladder subjects the lado der to a twisting strain which is damaging to the ladder. I

It is an object of this invention to provide readily adjustable extension members at the lower end portions of the side rails of a ladder to serve as feet for engaging the surface on which the ladder rests, said extension members extending beyond the bottom ends of the side rails and being adjustable longitudinally of the side rails whereby they may be positioned to rest squarely and evenly on an uneven or inclined supporting surface.

Another object of this invention is to provide a ladder foot extension having a base portion pivotally connected therewith and adapted to automatically adjust itself to conform to the surface on which it is placed.

Otherobjects of the invention are to provide ladder foot extension devices of strong and simple construction which are easily applied to an ordinary ladder and which are reliable and emcient in operation. 1

Other and more specific objects of the invention will be apparent from the following description taken in connection with the accompanying drawing.

In the drawing Figure 1 is a front elevation of the lower .end. portion of a ladder having these ladder foot extensions applied thereto, showing the ladder foot extensions resting on a sloping support, the upper end portion of the ladder being broken away.

Fig. 2 is a side elevation on a larger scale than Fig. 1, of one of the ladder foot extension devices. Fig. 3 is a vertical sectional view substantially on broken line 3-3 of Fig. 2, the two plates of the ladder foot extensionv member being shown spaced apart enough to clear the teeth thereof. Fig. 4 is a fragmentary sectional view, substantially on broken line 4-4 of Fig. 3, of the base portion of the ladder foot extension device.

Fig. 5 is a fragmentary view in elevation of a ladder foot extension member having a modified form of base member.

Fig. 6 is a fragmentary sectional view showing a cam and lever means for clamping two plate members together.

Fig. 7 is an elevation of the devices shown in Fig. 6.

Like reference numerals designate like parts throughout the several views.

Referring to the drawing, l0 and II designate 5 the side rails of an ordinary ladder of conventional form and I2 designates the usual rungs of the same.

A ladder foot extension device is shown operatively connected with each of the side rails I0 and H in Fig. 1. Each ladder foot extension device comprises an inner plate member l3 secured bybolts M to the adjacent side rail of the ladder and an outer plate member l5 cooperating with said inner plate member. The inner plate member I3 is provided with transversely extending ridges or teeth [6 of V shaped cross section extending across the outer side or face of said inner plate. Said inner plate I3 is further provided with a bolt member I! secured thereto near its lower end 'and projecting outwardly therefrom. The outer plate member I5 is provided with a longitudinally extending slot l8 fitting slidably over the bolt member I! and is further provided with transversely extending ridges or teeth IS on its 5 inner side which are adapted to interfit with the teth iii of the inner plate member i3. A nut 20, which is preferably a wing nut as threaded onto the bolt M for securely clamping the two plate members l3 and I5 together in any desired adjusted position. The lower end portion of the outer plate member l5 projects below the lower end of the side rail ID or H with which it is connected and preferably has a base member 2| pivotally connected therewith by means of a 5 shown, is

pivot bolt 22. The pivotal movement in both directions of the base member 2| on the outer plate member I! is limited by engagement of shoulders 23 with the end of the plate member I! as more clearly shown in Fig. 4. The base member 2i is self-adjusting on the bolt 22 so as to rest more squarely on a supporting surface than it-would if it was not pivotally mounted.

In Fig. 5 I have shown a fragment of an outer plate member which is similar to the plate member it except that it is provided with an integral base member 24 extending at substantially. right angles therefrom. The bottom surface of the base member 24 is preferably provided with transverse scores or ridges 25 so thatit will be -1ess liable to slide on a surface on which it rests.

The bottom surface of the base member 2| is preferably similarly scored as shown in Fig. 4.

In Figs. 6 and 7 I have shown a cam means for clamping the two plate members if and II together. When this cam means is used the clamping bolt 26 which is secured to the inner plate member if and passes through aslot in the outer plate member II is preferably flattened at its outer end and this flattened portion is positioned between two cam elements 21 which are integral with a cam lever 28. The cam elements 21 are pivoted on a pin 29 which passes through the bolt 26. The pin 29 is oi! center as respects the cam elements 21 so that when the cam lever 28 is in the position shown in Figs. 6 and 'I the cam' elements 21 will bear firmly against the outer plate member I! and clamp the; two plates tightly together". When the cam lever 28 is angularly moved clockwise from the position in which it is shown in Fig. 6 the cam members 2'! will be retracted from the plate II and sumcient clockwise movement of said cam lever will revices one of said devices is secured to the lower end portion of each side rail of a ladder, as shown in Fig. 1. When the ladder is to be supported on anuneven surface, as the surface Ill shown in Fig. 1, one of the outer plate members it will be extended far enough so that it will rest firmly on the supporting surface at a lower position than the other plate member. This provides a firm support for both side rails of the a mosa V v I ladder and obviates any. danger of said ladder tending to tip and fall due to inefiicient' support of one side rail. When the wing nut of the device shown in Figs. 1, 2 and 3 is tightened the teeth It and II will be held in tightly interfltting relation and there will be no tendency for the two side plates l8 and It to move either longitudinally or 'angularly relative to each other.

The foregoing description and accompanying drawing clearly disclose what I now regard as a preferred embodiment of my invention but it will be understood that this disclosure is merely illustrative and that such changes in the device may be made as are fairly within the scope and spirit of the following claims. I claim:

-1. The combination with the stiles of a ladder, of.a foot for each stile having a base portion to engagethe ground, a bolt pivotally mounting each foot on the respective stile to have a swinging movement in opposite directions across the end of the stile, said bolt. being disposed approximately midway of the length of said base portion and midway of the width of said stile, said end of each stile having a flat surface and said base portion of the foot having an inclined surface closely adjacent and at one side of the axial plane ofv the bolt that is perpendicular to the' plane of said base portion to engage said flat surface on the stile upon movementjof said base portion across the end of the stile in one direction,'whereby to limit relative movement of said stiles and said base portions in said direction and ensure a stable support of the ladder by said feet.

2. The combination with the stiles of a ladder, of a foot for each stile having a base. portion to engage the ground. a bolt pivotally mounting each foot on the respective stile to have a swinging movement in opposite directions across the end of the stile, said bolt being disposed approximately midway of the length of said base portion and midway of the width of said stile, said end of each stile having a flat surface and said base portion of the foot. having oppositely inclined surfaces disposed closely adjacent and at oppobase portion in opposite directions respectively,

whereby to limit relative movement of said stiles and said base portions in said directions and en-' sure a stable support for the ladder by said feet.

' mam: NOONE.