Convertible extension step-ladder.

Application filed September 28,1905.

Patented. Sept. 4,1906.

Serini Ko. 280,410.

. To all whom it may concern:

Be it known that I, Leonard M. Norton, a citizen of the United States of America, residing at Northampton, in the county of 5 .Hampshire and Commonwealth of Massachusetts, have invented a new and useful Convertible Extension Step-Ladder, of which the following is a specification.

My invention relates to improvements in io step-ladders of the extension variety, and comprises four separable or independent ladders or ladder-sections, together with attaching or connecting means, two of such sections being by preference provided with 15 steps and the other two with rungs and one of the step-sections having a platform at the top, all as hereinafter set forth.

The object of my invention is to provide a light, serviceable, and convenient, yet strong 20 and durable step-ladder which can be em. ployed as an ordinary step-ladder or extended to different heights, is capable of use under various conditions where it would not be possible or practicable to use the old form of 25 step-ladder, is convertible into two step-ladders each separate and distinct from the other, and may be disunited to furnish two entirely-separate extension-ladders or four segregated ladder-sections.

3° A further object of my invention is to afford simple and convenient means for permitting the various changes which such a step-ladder is capable of to be made with comparative ease and celerity.

I attain these objects by the means illustrated in the accompanying drawings, in which—

Figure 1 is a side elevation of the step-ladder complete, showing it closed or folded and 4° occupying the least possible space; Fig. 2, a similar view showing the same open, or, in other words, with the legs separated and in position for use like an ordinary step-ladder; Fig. 3, a side view of the step-ladder, one leg 45 being partly extended, an arrangement adapting it for use where one leg is to rest on a stair-tread or other elevation while the other leg rests upon the floor below; Fig. 4, side elevations of two step-ladders made out 5° of the one shown in the other views, with a platform supported thereby; Fig. 5, a sectional view of the step-ladder with the legs separated and both partly extended; Fig. 6, a front elevation of the step-ladder when arranged as it appears in Fig. 5, and Fig. 7 a 55 side elevation illustrating how the step-ladder can be placed against a perpendicular wall or the like.

Similar letters refer to similar parts throughout the several views. 60

This step-ladder consists, preferably, of four sections A, A', B, and B', each of the two former being made up of side rails a a, connected by steps δ, and. each of the two latter of side rails c c and rungs d. The sec- 65 tions A and B constitute what may be termed the “front” leg and the sections A' and B' the “back” leg. Permanently affixed to the top of the section A is a short platform e, mounted on joists//, rigidly at- 70 tached at their front ends to the side rails a of said section. Braces g g extend from the rear terminals of the joists / to the uppermost step δ of the section A to assist in supporting said joists and the platform e. The '75 back leg is pivotally attached to the joists/ ' by means of a pivot pin or bolt h, passing through holes in the upper ends of the side rails a of the section A' and through holes in said joists and in the braces g. One terminal 80 of the bolt h. is screw-threaded to receive a thumb-nut i outside of the adjacent rail a. The bolt h permits the legs to be swung toward and away from each other. Upon the removal of the thumb-nut i from the bolt h 85 the latter can be withdrawn from the joists/ and section A', so as to allow the back leg to be removed and the step-ladder to be converted into two extension-ladders or two independent step-ladders, as desired. 90

On the under side of each top and bottom step δ is a button j, arranged and adapted when turned crosswise of the step to project inward beyond the same. Two stirrups k are secured on the inner edge of each side 95 rail a near the top and bottom, the inwardlyprojecting curved portions thereof being adjacent the rear edges of the uppermost and . lowermost steps δ. These stirrups are designed to fit onto the rungs d and the buttons j 100 to engage the under sides of said rungs, as will be clearly seen upon referring to the drawings. Angular plates or clasps I are fastened to the side rails c of the sections A' and B' near their upper terminals and extend out- 105 wardly to receive the sections A and B. ,It β 830,485 will now be seen that when either of the lower buttons j is turned out of theway.of the rungs d of the adjacent section B or B' said section can be easily separated from the 5 upper section in the same leg sufficiently for said rungs to clear the associated stirrups k, moved up or down, accordingly as it is desired to shorten or lengthen the leg the requisite distance, and then again secured by clasping to the proper rung between said stirrups and button. There is sufficient looseness between the clasps Z and the upper sections to permit of the required amount of separation between such upper sections and the lower 15 sections so that the latter can be moved without their rungs catching upon the lower stirrups except at the proper time. The fastening means for the two sections of each leg just described is very safe and secure, also though simple and inexpensive. With the bolt /(. removed and the leg-sections unlocked said sections can be separated into four independent ladders.

Some suitable means, as the ordinary 25 hooks m and m' and staples n, may be provided for holding the legs of the step-ladder in place after being properly positioned and preventing them from further spreading apart.

In Figs. 1 and 2 the lowermost rungs d of the two sections B and B^z support the sections A and A! through the medium of the bottom stirrups k, the clasps Z assisting, the bottom button j in tins, as in all cases, merely 35 serving to prevent the engaging rungs and stirrups from becoming accidentally disconnected either while the device as a whole is being moved or at other times. In Fig. 3 the third rung from the bottom of the section B 40 forms the support in front and the lowermost rung of the section B' forms the support behind, thus producing a step-ladder with legs of unequal length adapted to stand upon different levels. The arrangement in Fig. 7, 45 where the supporting-rungs front and back are the second from the bottom of the section B and the lowermost of the section B', respectively, also produces a step-ladder with legs of unequal length, but which are adapted to stand on the same level, the back leg being vertical. Both legs are equally extended in Figs. 5 and 6, or substantially so, but not as much as they might be, into at least one rung front and back.

After disconnecting the legs each can be converted into a step-ladder by engaging the uppermost rung of the section B with the top stirrups k on the section A and the uppermost rung of the section B' with the top stirrups k on the section A', the top buttons j being now brought into service to prevent accidental displacement of the parts. By preference the section B is turned about, and so also is the ' section A', in order to bring the clasps Z into play as stops, as shown in Fig. 4, thus doing 65 away with any need of hooks, since one pair of said clasps contacts with the platform e and . the other pair with the upper terminals of the rails a of said section A'. It will be seen that one leg of each of these step-ladders is pro- 70 vided wi th steps and the other with rungs. A board or platform 0 is laid on the aforesaid independent step-ladders to form a staging.

No hooks or other equivalent fastening devices are required when the step-ladder is em- 7 5 ployed either as shoivn in Fig. 3 or Fig. 7.

It is a great advantage to have steps on both sections of the step-ladder upon which a person can stand to Avork—that is, the tAVO ripper sections—since tAvo persons are thus 80 enabled to stand comfortably thereon or one can work conveniently from either the front or back side thereof.

It is clear that the step-ladder can be arranged in various other forms and made the 85 subject of various other changes in addition to those illustrated, and it will be understood that much of its value resides in the many and different uses to Avhich it is applicable.

I am aware that extension step-ladders 90 have been produced before and do not seek to claim such a step-ladder, broadly; but

What I do claim as my invention, and desire to