US305347A

US305347A - Ladder

Info

Publication number: US305347A
Authority: US
Publication date: 1884-09-16
Anticipated expiration: 1901-09-16

Description

(No Model.)

F. E. A. SMITH.

LADDER.

Patented Sept. 16, 1884.

N0. 1305,3 47. R; v

UNITED STATES PATENT OFFICE.

FRANK A. SMITH, OF CHARLOTTE, MICHIGAN.

LADDER.

' SPECIFICATION forming part of Letters Patent No. 305,347, dated September 16, 1884:

V Application filed July 3, 1884. (No model.)

T 0 aZZ whom it may concern.- Be it known that I, FRANK E. A. SMITH, citizen'of the United States of America, residing at Charlotte, in the county of Eaton and State of Michigan, have invented certain new and useful Improvements in Ladders, of which the following is a specification, reference being had therein to the accompanying drawings.

The object of my invention is to produce a step-ladder which may also be employed as an ordinary extensible ladder; and it consists in the step-ladder A, having the supporting-hooks A, and ladder-section B, having guide-clamps G, and in the peculiar construction, combination, and arrangement of the parts, substantially as hereinafter more fully shown and described.

In the accompanying drawings, Figure 1 is a view in perspective of my invention. Fig. 2 is also a view in perspective showing the lower end of the lower or ladder-section broken away and the upper ladder-section extended and secured, and Fig. 3 is a detail view of my invention.

In the accompanying drawings, the letter A represents the steps of an ordinary step-ladder having the platform A, the longitudinal plates A and the supporting or splicing hooks A The steps A are mortised in the standards of the step-ladder, which standards are shouldered at top for thebetter support of the platform. The plates A are designed, in connection with studs 1) and the upper ladder-round, B, which fits into recesses a of standards a, to receive the spreading-strain of the two ladder-sections at the point of their connection. The supporting and splicing hooks A which are rigidly secured to the inner side of the ladder-standards a, where they come in contact with thefioor when the ladder is extended its full length, enlarge the base, and thus render more secure the support of the ladder, and when the ladder is extended its full length these hooks are projected over the next to the top round of the coincident ladder-section.

The guide clamps G, which are hanger shaped, their ends being bent at right angles, are rigidly secu'red to the ladder-section B. They project out horizontally when the ladder is in a vertical position, and their rightangular ends'project inwardly and over the edges of the standards a a of ladder-section A. Thus constructed, when it is desirable to employ a ladder to reach a greater altitude than can be reached by use of the stepladder, as shown in Fig. 1, section A of the extensible ladder is slid up into the position shown in Fig. 2, andthe hooks O are slipped down over a round of ladder-section B, as shown in Fig. 3, and the ladders, thus extended into a single ladder, are securely held in position by the joint action of the guide-clamps G and the supporting-hooks A I am aware that extensible ladders and stepladders are not broadly new, the same being shown in the patents of 'L. O. Boyington of September 25, 1877, No. 195,440, and G. A. Bourdman of October 11, 1881, No. 243,014, which I disclaim.

Having thus fully described my invention,

what I claim, and desire. to secure by Letters Patent, is-

The combination of the ladder-section A, having recesses 06, studs 1), and plates A and ladder-section B, having the right-angular hooks G, substantially as shown and described.

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

FRANK E. A. SMITH.

Witnesses:

JNo. B. BELCHER, JAs. G. POLLARD.