US426180A - Richard hammill - Google Patents

Description

(No Model.) R. HAMMILL.

LADDER.

No. 426,180. Patented Apr. 22. 1890.

irn TATES ATENT OFFICE.

RICHARD HAMMILL, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE HAMMILL FIRE ESCAPE COMPANY, OF SAME PLACE.

LADDER.

SPECIFICATION forming part of Letters Patent No. 426,180, dated April 22, 1890.

Application filed January 7,18 88.

To aZZ whom, it may concern:

Be it known that I, RICHARD HAMMILL, a citizen of the United States of America, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Ladders, of which the following is a specification, reference being had therein to the accompanying drawings.

IO This invention relates to ladders such as are adapted to be used in connection with buildings to effect a ready means of ingress and egress in time of fire or emergency of any nature.

The object of the invention is to provide a ladder that will be strong and durable, and which will be light and economical in its e011- struction and easily put together, and which will be self-sustaining, requiring no braces of any nature other than the rungs, which will be hereinafter more fully described and claimed, and shown in the annexed drawings, in which Figure 1 is a front view, parts being broken away, of a section of ladder embodying my invention; and Fig. 2, a cross-section of the ladder, showing a plan view of the rungs, the clamping-arms being shown extended by dotted lines.

The risers A A may be of an length, size, and form" in cross-section, and may be solid or tubular, the latter being preferable because of the lightness and strength of a tubular riser, and because ordinary gas and water pipes may be used.

The rungs B of cast metal have a broad head or cap D, which extends the entire length of the rung, and which is slightly curved on its upper surface in cross-section,

the said surface being roughened to prevent any accidental displacement or slipping of the foot. The vertical rib or fin (Z on the under side of each of the rungs strengthens them and admits of the cap-plate D being made exceedingly thin and light. The vertical extensions a at each end of the rungs have their outer sides parallel and adapted to fit against the risers throughout their length. These extensions a taper from their lower to their upper ends, which ends have clamping-armsc c, that are adapted to be bent about and embrace the risersA A. The

Serial No. 260,073. (No model.)

'bent to embrace the risers.

It will be observed that the vertical extensions a bear against the risers throughout their length. This is of vital importance, as it prevents any vertical movement of the risers and obviates the necessity of braces to steady them.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

1. As an improved article of manufacture, the hereinbefore shown and described malleable cast-metal rung for ladders, composed of the capplate D, roughened and curved on its upper surface in cross-section, the vertical fin or rib (Z, the vertical extensions (1. at its ends having their outer sides parallel and adapted to bear against the risers throughout their length, the clamping-arms c c at the upper ends of the extensions aand the lugs I) at a lowerlevel than the arms 0 c, substantantially as and for the purpose described.

2. The herein shown and described ladder, composed of the risers having openings in the sides at intervals and the malleable cast-metal rungs, each composed of the thin cap-plate D, roughened and curved 011 its upper surface in cross-section, the vertical rib or fin (Z, the vertical extensions to, tapering from bottom to top and bearing against the sides of the risers throughout their length, the clampingarms c c, bent about the risers, and the lugs b at a lower level than the said clamping arms, substantially as and for the purpose described.

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

RICHARD IIAMMILL.

Witnesses:

H. W. SMEAL, E. E. MoRRtLL.

Images