US916602A - Ladder. - Google Patents

Description

E. T.- ROBINSON;

Patented Mar. 3o, 1909.

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EARLE T. ROBINSON, OF ST. LOUIS, MISSOURI, ASSIGNOR TO ROBINSON FIRE APPARATUS MANUFACTURING COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION.

LADDER.

To all whom it may concern:

Be it known that I, EARLE T. ROBINSON, a citizen of the United States of America, residing in the city of St. Louis and State of Missouri, have invented certain new and useful Improvements in Ladders, of which the following is a full, clear, and exact description, reference being had to the accompanying drawing, forming part of this specification.

My invention relates to a new and useful improvement in ladders and particularly to that class having trussed side bars or rails, and has for its objects to produce a ladder of that character which will be very strong, durable, light and comparatively inexpensive to manufacture.

Figure I is a perspective view of a portion of a ladder having my improvements embodied therein. Fig. II is an enlarged detail view partly in side elevation and partly in section of a portion of my improved ladder. Fig. III is a section taken on the line III-III Fig. II. Fig. IV is a detail perspective view of one of the rung supports and bonds employed in carrying out my invention.

A represents the side bars, or rails, and B the rungs of my improved ladder. The side bars or rails A are each formed of a pair of longitudinal members a, c which are separated from each other by distance pieces A said distance pieces being of differential lengths, the smallest piece A being located at or near the ends of the members a', c, whence they gradually increase in length to the center thereof as is usual in ladders of this type.

1 re resents a rung support and bond, prefera ly made of metal which consists of a flat plate 2, having a hollow cylindrical body 3 conjoined thereto. The flat plate 2 is provided with a perforation 4 and spurs or lateral projections 5 and 6, said spurs 5 and 6 being formed respectively on opposite sides of the plate 2. The flat part 2 of these rung supports and bonds is interposed between one end of each of the distance pieces A and one of the longitudinal members a of the side bars of the ladder', with their spurs 5 and 6 fully embedded in the end of said distance ieces A and the members a respectively while the cylindrical body 3 of this support 1- Specification of Letters Patent.

Application filed. January 31, 1908.

Patented March 80, 1909.

Serial No. 413,513.

is caused to be located in the corner formed by the meeting faces of said distance pieces A and said members a.

7 designates a through bolt which passes through suitable alining bores formed 1n the members a, a, distance pieces A and through the perforation l formed in the flat plate 2 of the support 1, said through bolt being )referably provided upon one end with a liead and u )on its other end with screw threads, whichllatter are engaged by a suitable nut S, whereby, upon the proper adjusting of the same, the arts can be securely bound together. T ie rungs B are firmly secured in the hollow cylindrical body 3 in any suitable manner and when all of the arts are properly assembled, serve to tie I)both side bars A-A of the ladder together.

It will be observed that by the construction just described the part 1 not only serves as a rung receiver and support but that, through the virtue of its spurs 5 and 6, and the through bolt 7 in coperating with the members a, a. and the distance pieces A it serves as an adequate bond between the members a, a and the distance pieces A and insures against gyration of one with respee t to the other.

I claim:

1. In a ladder, trussed side bars-comprising longitudinal members separated by distance pieces, rung supports carried by said elements, through bolts securing the rung supports and distance pieces to said side bars, and rungs seated in said rung supports, substantially as set forth.

2. In a ladder, trussed side bars comprising longitudinal members separated by distance ieces, rung supports secured between said cistance pieces and said longitudinal members, through bolts tying said rung supports, distance pieces and longitudinal members together, means carried by said rung supports for preventing gyratory movement thereof and of said distance pieces, and rungs seated in said rung supports, substantially as set forth.

3. In a ladder, the combination with side bars, each comprising a pair of longitudinal members separated by distance pieces, of rung sup orts comprising flat perforated plates; said flat plates having spurs projecting laterally therefrom for engagement with one longitudinal member and one distance piece, and having conjoined thereto portions provided With cylindrical bores for the rcception of rungs of the ladder7 through bolts fastening said longitudinal members, each distance piece and rung support, together,

EARLE T. ROBINSON.

In presence of- BLANCHE HOGAN, H. G. Coon.

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