US170960A - Improvement in step-ladders - Google Patents

Description

' MVM/M@ NVPETERS, PHOTO-LITHOGRAPHER. WASHINGTON, D C k UNITED STATES PATENT OEEroEi MELVIN N. LOVELL, OF ERIE, PENNSYLVANIA.

IMPROVEMENT IN STEP-LADDERS.

Specication forming part of Letters Patent No. 170.960, dated December 14, 1875; application led January 23, 1875.

To all whom it may concern:

Be it known that I, MELVIN N. LovELL, of Erie, in the county of Erie and State of Penn- Sylvania7 have invented an Improved Step- Ladder, of which the following is a speciiication:

My invention consists in a new mode of constructing, and in a new arrangement of the parts of, a step-ladder as follows: first, in the form of construction of the steps and the manner of attaching the same to the stiles 5 second, in the manner of pivoting the swinging brace,

and of sustaining the same when extended.

My device is shown in the accompanying drawing, as follows: A is the top step, B B are the stiles, C C are the props or swinging brace, D D are the steps, E and F are crossstays, R R are rivets, and P is the pivot pin or bolt on which the swinging props are pivoted. The stiles B B are formed of two pieces or of one piece, which is opened by a saw-kerl', and then sprung apart as is very common in the construction-of step-ladders. I, however, prefer to make the stiles of two pieces thus bringing the opening between the said parts of the same width from top to bottom of the ladder, by which means I am enabled to make all the steps'exactly alike, except as to length. The stiles have a shallow mortise, b, and are provided with a rivethole, r, at the points where the steps D are to be connected. The steps D are provided with two mortises, d, at each end, for the reception of the stiles, and through the tenons thus formed is bored the rivet-hole r to correspond with the hole r in the stiles. The steps when in place are secured by a rivet, B, which passes through the stiles and step, and thus firmly holds it in place.

By this mode of construction and attachment no screws are used, and the steps are more firmly held in place than by the old methods, and the cost is less; and, also, by this method the steps are left the full width clear to the ends, and are supported there by the rivets, thus avoiding the danger of the edge of the steps being split off, as is the case Where the ends are chamfered oi, as in other forms of construction.

The cross-pieces E and F add to the strength of the ladder and furnish a rm support for the top step, and ample means for irmly attachin g the same to the ladder. These pieces, however, serve anothcrpurpose in my form of construction. They are projected beyond the sides of the stiles, and are so shaped that the swinging'props C, being pivoted between the same on the pivot-pin P, can be swung outward sufficiently to support the ladder, and are then stopped by the said projections e and f from further extension, thus avoiding the use of strings or other stays.

In order toA relieve the pi vot-pin P from sustaining the whole weight of the occupant of the ladder, and to bring that weight directly upon the end of the brace or prop C, I extend the same upward sufficiently to bring it in contact with the top step A; and in order to allow the brace C to swing the top step is out away on its under side at a, in such a way as to aiford a continuous bearing-that is, a bearing of the top step upon the prop C when at any angle or point of extension.

What I claim is as follows:

1. The steps D, in combination with the rivets R and stiles B B, substantially as shown, and for the purposes mentioned.

2. The combination ol' the crosspieces E and F, having extensions e and f, with the brace C, for the purposes mentioned.

MELVIN N. LOVELL.

Witnesses:

JOHN K. HALLocK, L. H. GoUsE.

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