US1251192A - Ladder extension. - Google Patents

Description

A. E. DRUMMOND,

LADDER EXTENSION.l

APPLICATION man MYI. 1911.

Pate/med Deo. 25, i917.

niurnn srarns PATENT onrron.

ABRAHAM ntnnuivnvronn, or srfiitnaroiv,` vInGmiA.

LADDER EXTENSION.

4To all whom t may concern.' v

.Be it known. thatl, Anaal-MM. E. DRUM- Moxn, a citizen of the United States,1residing` at Staunton, inthe county of Augusta and State offVirginia, have invented certain new andfuseful Improvements in Ladder Extensions; and I do Vdeclare the following to be a full, clear, ,and exact description of the invention, such asl will enable kothers skilled in the art to which vit appertains to make and usethe same. I

`My invention (relates to .that'class of devices intended for extending leither leg of a ladder so that the same may stand vertically on inclinedsurfaces. f

I am aware that devices for this purpose have heretofore been devised, but they have been more or less cumbersome and often prone to slip after adjust-ment, thus often causing the ladder and the. person thereon to fall.'V The principal object, therefore, is to provide a simple Iand inexpensive device which rwill be very'edective, there being no possibility whatever ofv the extension leg slipping `after it is once adjusted.

Anotherobject is t@ .provide a device Vof the class described which will be applicable to ordinary ladders without changing the construction thereofin any way.

Yetanother object is to provide an eXtension leg which may be used on either leg of the ladder. Y

With the foregoing lgeneral objects in view, the invention resides in the novel yfeatures of construction and unique combinations of parts to behereinafter/fully described and claimed, thedescriptive matter being supplemented by the accompanying drawing which constitutes a part of this afpplica-tion and in which:

Figure 1 is a side elevation of a ladder, showing the application of the invention;

Fig. 2 is an edge view of Fig. 1;

Fig. 3 is a vertical section through the attachment on the plane of the line 3 3 of Fig. 2;

Figs. 4 and 5 are horizontal sections on the planes of the lines 4-4 and 5--5 respectively of Fig. 2;

Figs. 6 and 7 are horizontal sectional views on the planes indicated by the lines 6 6 and 7-7 of Fig. 3.

In the drawings above briefly described, the numerals 1 designate the legs of a common type of ladder, the usual rounds or rungs 2 being provided between said legs.

Patented Dec, 25,51917.

Application led May 7, 1917. Serial No. 167,109.

It often occurs vthat vthe ladder must be used on inclined or irregular surfaces so that the lower endsof both. legs do not rest` solidly,

and in order to overcome the defect, an exe tension leg 3 is provided, the present inventionY consisting in themanner of attaching said leg Vand securing the same in adjusted position. j

A channel-iron bar 4 is provided, in the upper'end of its closed side, with aver-tical notch 5 while the lower end of said baris equipped with a socket 6to receivethe lower end of either leg of the ladder, said socket being formed by a rectangular band 7 passingaround the lower end of the bar 4 and spaced from the body portion thereof, said band being riveted or otherwise secured in place and having on its lower edge a flange S which is bent to a horizontal position to form the bottom of the socket. When either ladder., leg vis received inthe socket @,the upper end AO ffthe channel barl 4 is held in place by a bolt or the like, 9 preferably having awing nut 10, one bolt being in most cases provided for each leg. The bolts 9 preferably Apass through-.washers 11 inset in the outer sides of They extension'legs 3 are received slide ablyin the channel-'bars 4 and at their-lower endsfalezheld yagainst lateral ydisplacement bytthe' bands, the upper ends'ofsaid eX- tension legs, however, being secured in place by meansof a pair of locking bolts 12 having reduced. outer ends v13 for vreception ingvertically 'spaced openings; 14 yformed in the side flanges of the channel bar 4. The bolts 12 are received in alined tubular guides 15 formed by bending the upper end of a plate 16 as shown, said plate being secured to the upper end of the extension leg 3 by screws or other appropriate fasteners. The inner ends of the guides 15 are beveled to form a pair of cam-like edges 17 which converge toward their upper ends and are here provided with notches or seats 18 for a purpose tobe described.

A substantially V-shaped wire spring 19 is secured at the free ends of its arms to the bolts 12 as depicted most clearly in Figs, 2, 3 and 4, said arms abutting thecamlike edges 17 and serving to normally force f tion.

cause the two arms of said spring to move inwardly to withdraw both bolts, whereupon the extension leg '3 may be adjusted as required. Vhen the spring is thrown upwardly to its limit, the arms thereof will snap into the seats or notches 18 and thus the bolts will be held retracted While adjustment of the extension leg is being made.

From the foregoing, taken in connection with the accompanying drawing, it Will be obvious that although the invention is of extremely simple and inexpensive nature, it will be highly eiiicient and positive in action, the device being applicable equally Well to either leg of the ladder and since the socket 6, is of suHicient size, the device may be applied easily, even though the rounds 2 eX- tend a slight distance beyond the outer sides of the legs, or if said sides belencumbered. with other projections. j

Since probably the best results are obtained from the specific construction shown, such construction constitutes the preferred form of the device, but l wish it understood, however, that within the scope of the invention as claimed, numerous minor changes may be made without sacricing the principal advantages.

I claim:

l. An extension leg combination for ladders comprising a channel-bar having at its lower end a socket adjacent its closed side to receive the lower end of the ladder leg, said socket having a bottom upon which said ladder leg rests, the upper end-of said bar having aA vertical notch, a bolt passing .through said notch and adapted for passage through said leg to secure the upper end of said bar in position, an extension' leg slidable in said channel-bar, and means for securing said extension leg in adjusted posi- 2. An extension leg combination for ladders comprising a vertical channel-bar, means for securing the upper end of said bar to a ladder leg, a band passing around the lower end of said bar and secured thereto, said band being spaced from the closed side of said bar and being formed on the lower edge with a flange extending toward said closed side, whereby a socket having a bottom is provided to receive the lower end of the ladder leg, an extension leg received slidably in said channel-bar and held against lateral displacement by said band, and means for-securing said extension leg in adjusted position.

3. An extension leg combination for ladders comprising a vertical channel-shaped guide having vertically spaced openings in its side flanges, an extension leg slidable vertically in said guide, a pair of alined tubular guides carried rigidly by said leg and having converging cam-like edges, cams at their inner ends, a pair of alined bolts slidablein said tubular guides and adapted for reception in any of said openings, and a substantially V-shaped spring Whose arms are secured to said bolts, said arms bearing against said cam-like edges.

4. An extension leg combination for ladders, comprising a channel bar and means for securing it to one of the ladder legs, both side flanges of said channel bar having vertically spaced openings', an extension leg slidably received in the channel of said channel bar, and oppositely extending bolts mounted on said extension leg and receivable in said openings to hold said extension leg in vertically adjusted position, together with means for simultaneously projecting both bolts.

In testimony whereofl have hereunto set my hand in the presence of two subscribing witnesses. i

ABRAHAM E. DRUMMOND.

yliitnessesz. l

C.- W. HINER, Trios. T. GLENN.

Copies of this patent may be obtained for ve cents each, by addressing the-fGommissioner ot Patents, Washington, D. C,

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