US151429A - Improvement in firemen s ladders - Google Patents

Description

T. PRITCHARD.

Firemens Ladders. N0.151,429, Patented May 26,1874.

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THOMAS PRITOHABD, OF PHILADELPHIA PENNSYLVANIA.

IMPROVEMENT IN FIREMENS LADDERS.

Specification forming part of Letters Patent No. 151,429, dated May 26,1874; application filed March 10, 1874.

To all whom it may concern:

Be it known that I, THOMAS PRITCHARD, of Philadelphia, Pennsylvania, have invented a Combined Ladder and Truck, of which the following is a specfication:

The objects of my invention are to avoid the usual necessity in elevating firemens ladders, of placing them against buildings, and to provide an wefiicient and readily-operated fire-escape.

I attain these objects by hinging the ladder B, at its base, to a platform, D, pivoted to a truck, A, as shown in the perspective view, Figure l of the accompanying drawing, so that the said ladder, which is provided with extension-legs E and adjustable platforms F, can be raised and lowered on the truck, and can be turned laterally in any dirrgotion, and secured, as fully explained herea 'ter.

The truck A is mounted upon wheels to, and in suitable bearings b, at or near one end of the truck, turns a transverse shaft, cl, to which the base of the ladder B is firmly scoured, the latter, when depressed, resting upon blocks 0 at the opposite end of the truck. At one end of the shaft (1 is a wormwheel, f, into which gears a worm, g, on a short spindle, j, adapted to bearings on the truck. The spindle j is provided with a crank or key, by turning which the ladder may be elevated through the medium of the worm and wheel, the latter also eifectually locking and preventing the accidental descent of the ladder.

The ladder can be ascended and descended with safety when supported by the worm and wheel only; but, in order to reduce the strain upon the latter, I propose, in most instances, to use extension-legs E, attached to the ladder at or near its upper end, and resting at their lower ends upon the ground or other suitable support, the legs being carried by and effectually bracing the ladder, whatever may be its position in respect to the truck.

These extension-legs may be variously constructed; but I prefer to use tubes 70, pivoted to the ladder at l, and provided with internal sliding rods m, which, after having drawn out to the proper extent, are secured by setscrews n.

The extension-rods, when not required for use, are drawn in against the side rails of the ladder, and secured thereto in any suitable manner.

In order to afford a good foot-hold for the fireman, and for those escaping from burning buildings, I propose to combine one or more platforms, F, with the ladder, as shown in the drawings. These platforms are hinged at p to the rungs of the ladder, upon which they can be freely turned; and after the ladder has been raised and secured at the desired inclination, the said platforms can be turned to a horizontal position, and thus retained by chains q suspended from the ladder, and hooked to their outer edges.

The enlarged sectional view, Fig.2, shows the mechanism for raising and lowering the ladder, and for turning the pivoted platform. The latter consists of a wornrwheel, 2 secured to the underside of the platform, and turned by a worm, h, on a spindle, h, which has its bearings in the truck. This gear, like that for raising and lowering the ladder, has the advantage of locking and preventing accidental movement of the pivoted platform.

WVithout claiming, broadly, a ladder, hinged at its lower end to a truck; the combination, with the ladder, of a horizontal platform, to which the ladder is pivoted; or the combination, with a ladder, of adjustable legs I claim as my invention 1. The combination of a ladder, hinged at its lower end to a truck, a worm-wheel secured to the ladder, and an operating worm, all as and for the purpose specified.

2. The combination of the horizontal plat form I), pivoted to the truck, and to which a ladder is hinged, and the worm h and wormwheel 2', all as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

THOMAS PRITOHARD. Witnesses:

WM. A. STEEL, HARRY SMITH,

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