US101943A - Improved ladder - Google Patents

Description

tlnitrd tant @aient Gtiijiw.

Letters Paten-t No. 101,943, dated April 12, 1870; antedatvell April 1,1870.

IMPROVE!) LADDER.

The .Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern:

ydrawings making a part ofthis specification, and to the letters of, reference marked thereon, like letters indicating like parts wherever they occur.

To enableothers skilled in the art to construct and use my invention, I will'v proceed to describe it.

My invention consists in certain improvements in round and step-ladders, whereby greater lightness is secured, and their strength is increased.

Figure lisa perspective View of a round-ladder.

Figure 2, a similar View of a step-ladder.

Y Figures 3 3, view of metallic locks.

Figure 4, view of back braces.

Figure 5 shows the mode of attaching cord.

To secure lightness, I construct the rails of my ladder A A of angle form, sawing out a portion of the wood, as seen in igs. 1 and 2. For the same purpose Ilsplit the plank for the step, as-shown in g. 2, H H, thus increasing their strengthin front when the weight is applied inrascending and descending, leaving the back of the step thin and light. The step and round are framed to t 'the angle of the rail, as seen in gures, and locked to -the rails-by means of the metal corner locks L L, which are -held to step, round, and rail by wood screws O passing through the rail and -lock andinto the round or step. The lock is secured to step and rou-nd -on their under sides, making a firm support for the round and step, and binding the rail and step rm without weakening the rail.

'lo add to the strength of long step and round'laddeis, I spring a cord, J, of fine-twisted wire from top to bottom upon the back of the ladders, as shown at' fig. 1, J. This cord is made tense by passing over suitable saddle pillars-I, rising from the rail oi' the ladders, and braced and tied by cross-ties, so the cords cannot be thrown off while the weight is applied.

As a security while ascending or descending long ladders, I attach firmly to the top ofthe outer rails of the ladder similar metal cords, of greater length than the rails, armed with suitable grappling hooks or pins, by means of which the lower ends of the stay cords may be held firm tothe earth or to buildings,.thus securing the ladder from falling sidewise or-forwarih The back braces of -the step-ladders, B, are also made of rails, constructed similar, and may be hinged as shown in iig. 4, with double-acting hinges, or by passing a rod from brace to brace von top, and applying the hinge to the outside of the braces. These bracesare spread out or closed, and held by means of the curved ties, lock, and pin.

Having-thus described my invention,

Al. In a round or step-ladder, the angle bars or rails, whether made of wood or metal, when arranged for the reception and support of the round or step, as and for the purposes set forth.

2. Incombiuation with the described bars and the rounds or steps, the metallic lock rests, when constructed as and for the purposes set forth.

3. rIhe described round and step-ladder, composed ofthe angle bars A, rounds H H o'r steps H H, with the described lock rests, all constructed and arranged as and for the purposes set forth.

4. The peculiar construction of the steps H H from` a simple plank, when arranged with the thick edges on the front side, for the purposes set forth.

5. The described ladders', composed of the side bars A, steps H, lock rests L, hinged braces, with their adjustable cross-connections G O, and double-acting hinges M, all arranged and operating as and for the purposes set fortlul Witnesses: JOHN A. THOMPSON.

EDM. F. BROWN, O. Bns'ron.

Images