US595935A

US595935A - Extension step-ladder

Info

Publication number: US595935A
Authority: US
Publication date: 1897-12-21
Anticipated expiration: 1914-12-21

Description

(No Model.)

D.BBRNHART. EXTENSION STEP LADDER.

' Patented Dec. 21,1897.

UNITED STATES PATENT OFFICE.

DANIEL BERNHART, OF PITTSBURG, PENNSYLVANIA.

EXTENSION STEP-LADDER.

SPECIFICATION forming part of Letters Patent No. 595,935, dated December 21, 1897.

Application filed November 13,1896. Serial No. 611,957- (No model.) I

To all whom it may concern:

Be it known that I, DANIEL BERNHART, a citizen of the United States of America, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have in-.

Y ladder being used on the steps of a house or the like, which is impossible with the ordinary step-ladder.

The invention further aims to construct a step-ladder combining the above advantages that will be extremely simple in its construction, strong, durable, effectual in its operation, and comparatively inexpensive to manufacture.

With the above and other objects in view the invention finally consists in the novel construction, combination, and arrangement of parts to be hereinafter more specifically described, and particularly pointed out in the claims.

In describing the invention in detail reference is had to the accompanying drawings, forming a part of this specification, and wherein like letters of reference indicate similar parts throughout the several views, in which- Figure 1 is a front elevation of my improved extension step-ladder. Fig. 2 is a side elevation of the same. Fig. 3 is a view of a portion of the rear support in the extended position. Fig. 4 is a longitudinal sectional view of a portion of the brace-bars. Fig. 5 is a side view of the hinged securing-clamp.

a a represent the front standards,the standard a being shorter than the one a. Secured to the lower end of the standard a is the clamp b, in which is secured the extension bar or foot 0 by means of a set-screw d. The standard a is also provided near its base with a similar extension bar or foot 0, secured in.

a clamp 19 by means of a set-screw d. The standards a a are connected by means of the rungs a and are provided at their ends with a V-shaped groove to receive the lower ends of the front standards 6, connected at their tops by the cross-board f. The braces g are pivotallysecured to the standards 6 near their bases and to the standards a a near their tops and which loosely connect the standards and permit them to be folded, as shown in dotted lines in Fig. 2. To the standards a. a are rigidly secured the stops h, which extend above the joint between the standards a a and e, and which stops serve to limit the movement of the braces y when the two supports or standards are in line with each other. A hinged clamp is secured to each of the standards a, and which clamps close over the braces g, as shown in Fig. 2, for the purpose of locking'the parts securely in position.

The braces Z are secured to the upper ends of the standards 6 and to the top board f, and to the rear ends of these braces are secured the supports m, which are pivoted to the braces Z in such a manner as to permit the folding of the ladder. These rear supports, as shown in Figs. 2 and 4:, are secured in their positions in the same manner as the front standards. The upper supports m have V-shaped ends to engaget-he grooves in the top of the lower supports 71.. To both the supports m and n are pivoted side braces 0, which extend across the joint between the two parts and which are provided with holes 19 to receive the pins for locking the supports rigidly in position. When the ladder is folded, the braces g and o assume the position shown in dotted lines in Fig. 2. K

The supports n are each provided with an extension-foot 0 secured by means of a clamp b and set-screw 01 as upon the front standards. The supports m and n are connected in pairs by the cross-braces r and s.

The front and rear portions of the ladder are connected by the pivoted braces t and said braces t carrying the clamp 27, provided with the pin i and which pin engages the brace 15, thus permitting the braces to fold. The keeper holds the braces together.

In order to lower the ladder from the extended form, as shown in Figs. 1 and 2, to

the position shown in dotted lines in Fig; 2, the hinged clamp It is thrown open to release the front standards, the keeper t is pushed out of engagement with the cross-bar i, and the pins in the braces 0 removed. The upper portion of the ladder can then be lifted or swung out of engagement with the lower portion and folded down, as shown in the dotted lines in Fig. 2.

The extension-feet employed at the base of the supports will admit of one side being lengthened to conform to an uneven surface, and by shortening the supports by means of these extension-feet the support can be placed 011 a step with the main portion below the step.

Having thus described my invention, I claim 1. In a step-ladder, the front and rear standards, each made in two parts, the lower portions being provided with stop-braces h h, combined with the braces g, 0, pivoted at their ends to the parts of the standards, so as to act as hinges for connecting them, and pivoted latches applied to the standards, and which close over the braces g, substantially as described.

2. In a step-ladder, the front and rear standards, each made in two parts, and the lower parts provided with stop-braces, combined with the braces 9,0, pivoted at their ends to the parts of the standards, and which act as hinges to connect the parts, and which are limited in their upward movement by the stop-braces, a hinged catch for catching over the braces, and the braces I t, loosely connected at their inner ends, and to the standards at their outer ends, substantially as set forth.

In testimony whereof I aflix my signature in presence of two witnesses.

DANIEL BERNI'IART.

Witnesses A. M. WILsoN, II. E. SEIBERT.