US178480A - Improvement in extension-ladders - Google Patents

Description

R. G. SPAULDING.

EXTENSION-LADDER.

No.173,4:80. v Patented June6,1876.

UNITED STATES PATENT QEECE.

ROSWELL Gr. SPAULDING, OF JONESVILLE, MICHIGAN.

IMPROVEMENT IN EXTENSION-LADDERS.

Specification forming part of Letters Patent No. 178,480., dated J une 6, 1876 application filed May 3, 1876.

To all whom 'it may concerti:

Be it known that I, RosvvELL G. SPAULD- ING, ot' Jonesville, in the county of Hills- .dale and State of Michigan, have invented an Improvement in Extension-Ladders, of which the following is a specication:

The nature of my invention relates to an improvement in 'extension-ladders of that class in which the `sections are adapted to be locked one onto another until the required length ot' ladder is attained.

The invention consists in the novel and peculiar construction ot' the parts for locking the sections together, as more fully hereinafter set forth.

Figure l is a sectional elevation of parts of two ladder-sections locked together. Fig. 2 isa perspective viewL ot' the outer side of a section at the top thereof. Fig. 3 `is a similar view ot' the inner side of a section at the foot thereof'.

In the drawing, A A represent sections of a tapering ladder, the head of one section adapted to enter the foot of' the other. The rounds of' the ladder-sections are of Wood, and below the round, next the toot of each section, there is an iron rod, a, which binds the sides together. Just below the top round there is a similar Vgirt-round, b, whose ends project, each terminating in a head, c. Bis a metal plate, fastened to the outer face of each side har at the top, with a slot, d, cut down in both to receive the lower round and rod a of a section that may be slipped on. The inside ot' the foot of each side bar of a section is faced, in like manner, by a metal plate, B', having a slot, e, cut in it to slip over the protruding end of the girt-round b, whose head c passes behind the said plate in a groove cut in the side bar. which not only prevents the foot from spreading, but, with the upper joint, serves to lock the two sections rigidly together.

rEhe sections may be prevented from pulling apart by a screw-holt, C, tapped through a nut, e', let into each section near the top, to enter a socket in the foot ot' the section above.

With three sections of the several lengths of eleven, fourteen, and seventeen feet, a height ot' forty feet may be reached, and, by varying the combinations of sections, seven different lengths of ladder can be had.

Owing to its ease of adjustment, great strength ot'joints, and facility with which any length of ladder Within the limit ot' total length can be had, this ladder is especially adapted for use in fire departments, house painting, and in other operations Where strength and rapid adjustment are required.

What I claim as my invention isl. A ladder-section, A, having the metal round a at the foot, the metal round b c near the top, and the slotted metal plates B B', as and for the purpose set forth.

2. The screw-bolt U and nut c in the upper part of each ladder-section A, for securing two such sections together, substantially as described.

ROSWELL G. SPAULDING. Witnesses JOHN T.` BLoIs, GEORGE W. BAKER.

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