US1274683A - Step-ladder. - Google Patents

Description

A. L. CHAMPION.

STEP LADDERi APPLYCATION mm) mm: 6.191].

, Patented Aug. 6, 1918.

2 SHEETSSHEET 1 avwemtoz v A. LLCHAMPION.

STEP LADDER.

APPLICATI ON FILED JUNE 8, I9! 7.

Patented Aug. 6, 1918.

ABRAHAM LINCOLN CHAMPION, 015 BOSTON, MASSACHUSETTS.

STEP-LADDER!- Application filed June 8, 1917.

To all whom it may concern:

Be it known that LABRAHAM LINCOLN CHAMPION, a citizen of the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Step-Ladders; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

' This invention relates to step ladders and more particularly to that type which are adjustable to different heights.

An objectof this invention is to provide an adjustable ladder which may be used with safety on stairways or on other places having uneven surfaces.

Another object is to provide a ladder which may be used equally well on stairs having steep steps or low, broad steps.

Other objects will appear as the description proceeds.

In the drawings like reference characters are used to designate corresponding parts.

Figure 1 is a side elevation;

Fig. 2 is a rear edge view;

Fig. 3 is a central vertical section on line 33 of Fig. 2;

Fig. 4 is a horizontal section on the line 4-4: of Fig. 3;

Fig. 5 is a vertical horizontal section on the line 5-5 of Fig. 3;

Fig. 6 is a perspective view of one of the braces, the same being disconnected; and

Fig. 7 is a similar view, showing the members in operative position.

The ladder proper 1 has side bars 2 and a series of steps 3 secured thereto in the usual manner. Fastened to the inner sides 2 of the ladder 1 just below the top step or platform 4 are two parallel brackets 5, formed with bearings 6 for a transverse shaft 7, the ends of which extend laterally beyond the brackets 5 to serve as pivotal supports for the supporting legs 8 of the ladder, the upper ends of which are formed with openings to receive the ends of the shaft 7.

Each side bar or leg 2 is provided with a longitudinal slot 9 which is countersunk at the inner side of the leg; and extension legs lO-which extend parallel to the legs 2 and in contact with the outer sides thereof,

Specification of Letters Patent. Patented Aug. 6, 1918.

Serial No. 173,613.

are provided with elongated slots 11 which register with the slots 9. Clamping bolts 12 pass through the upper ends of the extension legslO and through the slot 9 and are held in clamping position by wing nuts 18, said bolts having conical heads 12 seated in the countersunk slots 9 for free sliding without engagement with the steps 3, which steps span the slots 9 and tend to prevent splitting of the legs 2. The lower end of said legs 2 are provided with bolts 14 having elongated heads 1%, said bolts passing through said legs and extending laterally therefrom through the slots 11 in the exten sion legs 10, being held in clamping position by wing nuts 15. Particular emphasis is laid upon the fact that the steps 3 prevent splitting of the legs 2 by spanning the slots 9, and upon the fact that these steps do not interrupt the movement of the bolt heads 12', due to the countersunk formation of said slots and to the conical shape of said heads. I

The supporting legs 8 are pivotally mounted on the shaft 7, which is journaled in bearings 6 which are carried by the brackets 5. These legs 8 are provided with elongated slots 16, having beveled edges, and have bracing rods 17 and 18 positioned above and below the slots 16, respectively. Parallel. with the legs 8 and outside of the same are sections 19, which are provided with elongated slots 20, registering with the slots 16 in the legs 8. Bolts 21 having enlarged U-shaped heads 21 are positioned in the lower ends of the legs 8 and pass through the slots 20, and are held in position by clamping nuts 22, preferably of the butterfly form. The upper ends of the sections 19 are also provided with bolts 23 which pass through them and extend laterally through the slots 16 in the side bars 8, and are held in position by the nuts 24, preferably of the butterfly type. The heads of the bolts 23 engage the beveled edges of the slots 16.

Braces 25, each comprising two like members 26 and 27 are loosely pivoted to the inner edges of the side bars 2 and the supporting legs 8. These members 26 and 27 are substantially rectangular and have a stud or projection 28 extending at right angles from their ends. Each member also is provided with openings 29, which are adapted to receive the projections 28 when the braces 25 are in operative position. It will be seen that the projection 011 one member will pass through an opening on the other member, and vice-versa.

A pivoted fastener 30 is carried-n member 27 and is used to hold the members 27 and 28 in engagement when in operative position. It is to be understood that any form of fastener may be employed, which will serve the purpose. \Vhen the ladder l is in closed position, the members and 27 are unlastened and hang loosely inside the side bars :2 and legs 8.

The ladder may be used 011 a stairway with the steps of the ladder parallel to the steps of the stairway by drawing outwardly either set of extension members or 19 as required.

The ladder may be used equally well transversely of the steps, by lowering the supplementary legs of the side bar and prop sections nearest the lower side of the steps.

Various changes in form, proportion, and in the minor details of construction may. be

resorted to without departing from the spirit of this invention.

I claim In an extension leg for ladders, the combination of apair of flat vertical ladder legs each having a longitudinal slot countersunk at the-inner side of the leg, steps extending between said legs and secured thereto, the ends oi" said steps spanning said slots, a pair of extension legs contacting slidably with the outer sides of said ladder legs, clan'iping bolts passing through said extensionlegs and having conical heads seated in said countersunk slots for free sliding without contact with the ends of said steps, and means for preventing said extension legs from pivoting around'said clamping bolts.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

ABRAHAM LINCOLN CHAMPION.

\Vitnesses FLORENCE E. LEE,

ROBERT L. Mnnarr'r, Jr.

Copies of this patent may be obtained'for five cents each,- by: addressing, the "Commissioner of Patents,

Washington, D.-G.

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