US278051A

US278051A - Ladder

Info

Publication number: US278051A
Authority: US
Publication date: 1883-05-22
Anticipated expiration: 1900-05-22

Description

(No Model.)

F. S. SEAGRAVE.

LADDER.

Patented May 22,1883.

proved ladder.

showing the method of constructing each leg- UNITED STATES PATENT OFFICE.

FREDERIG S. SEAGRAVE, OF ROCHESTER, MICHIGAN.

LADDER.

SPECIFICATION forming part of Letters Patent No. 278,051, dated May 22, 1883.

Application filed November 8, 1882. (No model.)

To all whom it may concern:

Be it known that I, FREDERIG S. SEAGRAVE, of Rochester, inthe county of Oakland and State of Michigan, have invented new and usefulIm provements in -Ladders and I do hereby declare that the following is a full, clear, and exact description thereof, reference being bad to the accompanying drawings, which form a part of this specification.

The nature of this invention relates to certain new and useful improvements in ladders, bymeans of which a'very light, strong, and durable ladder is constructed.

The invention consists in the peculiar construction of parts and their combination, as more fully hereinafter described.

Figure l is a perspective view of my im- Fig. 2 is a side elevation,

of the ladder, with its truss, from a single piece of lumber.

In the accompanying drawings, which form a part of this specification, A represents the legs of a ladder, which arejoined together by the rounds B in the usual manner. 0 is the truss with which each leg is provided, and D are the struts.

The peculiarity of this ladder is in the construction of the legs and trusses. In Fig. 2 there is shown a straight piece of timber, of the desired length of the ladder, near one end, and at the rear end of this piece thereis bored at small hole, a, through which a saw is inserted, which cuts the saw-kerf b, which extends nearly to the opposite end of this piece of timber. This rear piece thus partially de- 'tached from the main piece ofthe leg is thinner than and forms an integral part of theleg itself, and bolts 0 are inserted through the leg from front to rear, just at the ends of the sawkerf, to prevent splitting at that point. The two legs being thus prepared, and being joined together by the rounds, the struts are inserted between the leg proper and the truss, the longer one at a nearly-central position between the two ends, and the shorter ones intermediate between the longer strut and the ends of the legs, and these struts are secured in posiladders; and I am also aware that light andvery strong ladders are made which are trussed with wire, which makes them more expensive in construction and less firm than when made as I have before described, for such wire trusses will stretch, or, to use a technical phrase, give and take-'-a fault which is entirely avoided by my construction.

An ordinary painters ladder twenty-five feet long requires sixty feet of lumber to construct it, while an equally strong but much lighter ladder can be made, by the construction herein described, of the same length with lifteen feet of lumber.

What I claim as my invention is l. The combinatioiuin aladder, ofthe rounds B and legs A, each leg being provided with a kerf, I), back of its center, and extending nearly to the ends thereof, forming a thin back or brace, 0, whereby the front A, or leg proper, is left sufliciently thick for, the insertion of the rounds B, as set forth.

2. A ladder constructed of sides or legs A, having a brace, (l, formed by a kerf. I), in the leg, back of its center, as shown and described, rounds B, struts D, and bolts 0, all constructed and arranged substantially as shown and described.

FREDERIG S. SEAGRAVE.

Witnesses:

H. S. SPR-AGUE,

' A. BARTHEL.