US712262A - Tilting extension for fire-escapes. - Google Patents

Description

M.V CODY.

Patented om. 28, |902.

TILTING EXTENSION FDR FIRE ESCAPIES.

NITED, STATES PATENT OFFICE.

MICHAEL conv, OF CHICAGO, ILLINOIS.

TILTING EXTENSION FOR FIRE-ESVCAPES.

SPECIFICATION forming part of Letters Patent No. 712,262, dated October 28, 1902. Application led May 31, 1902. Serial No. 109,702. l(No model.)

To all whom it may concern:

Beit known that I, MICHAEL Conv, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Tilting Extensions for Fire-Escapes, of which the following is al specification.

My invention relates to certain improvements in fire-escapes, and has reference more particularly to an imprpved tilting stairway or ladder designed to form a connection between the lower platform or balcony of an Ordinary stationary fire-escape, which is usually located on the level with the second story of a building, and the sidewalk or ground surface therebeneath. Stationary fire-escapes of that class which are applied to the-external walls of officebuildings, apartment-houses, and like structures usually terminate at the second story of the building, for the reason that if extended entirely to the ground they would occupy space required for other purposes. VIn view have been proposed and employed in connec-V tion with and as an adjunct to the stationary structure of the escape, and Iny invention has to do with this last-mentioned class'of devices, its principal object being to provide an improved pivoted extension designed to aord a connection between the lowermost stationary platform or balcony and the ground when such a connection is required and to be tilted up out ofv the way of passers-by at all other times.

More specifically, my invention relates to a novel and improved means for counterbalancing the pivoted section in such a way that the laddermay be raised and lowered with the application of but a slight impluse in either direction, and, furthermore, may be lowered into operative position automatically, as it were, by which I mean that the mere act of the individual descending the same in stepping from the stationary platform Onto the topmost step of the ladder will depress the latter and that so gradually as to avoid all danger of a fall on the part of the person descending the same.

To these and other minor ends my invention consists in an improved tilting ladder or o, stairway constituting the lowermost extension of a stationary fire-escape having the y peculiar and novel features of construction and mode of operation, substantially as here- 6o inafter described, and pointed out in the claims.

In the accompanying drawings,which illustrate the preferred embodiment of my invention, Figure 1 is a side elevational view of my 65 improved tilting stairway, the same being shown as connected to the lowermost platform of a stationary fire-escape, the full linesl indicating its lowered or operative position and the dotted lines representingits elevated 7o or idle position. Fig. 2 is a top plan View of the same, and Fig. 3 is a transverse vertical sectional view on the line 3 3 Of-Fig. 1 looking in the direction of thearrow.

-Referring to the drawings, f1 designates the 75 lower platform or balcony of a stationary iirep escape, such as is commonly applied to the external walls, as 5, of high buildings, and 6 indicates a vertical bracket which in copplatform 4, is a short stairway or ladder 8,

lwhich is preferably provided with a hand-rail 9 and the upper end of which has a substan- Itially horizontal extension 10, the outer end of which supports a stirrup 11 for a purpose hereinafter disclosed. Likewise pivoted upon the rod 7 and between the side rails of the 9o stairway is a box or casing 12, the bottom or lower wall of which is longitudinally slotted throughout the major portion thereof, as shown at 13 in Eig. 3, thereby providing a pair of inwardly-projecting flanges 14, that constitute a track or way upon which may roll back and forth a counterweight in the n nature of a heavy metal ball 15. It will be' observed that the casing 12 is formed on the line of an arc of a circle, whereby the way or roo track 14 is slightly curved in a vertical plane between the opposite ends of the casing. This is for a purpose which will appear in connection with the description of the operation of the device. The casing 12 is hinged through the upper portion of its inner end relatively to its supporting parts, while its outer portion seats in and is supported by the stirrup 11, carried by and between the rearward extensions 10 of the side members of the stairway.

The operation of the device is substantially as follows: The stairway is normally in the idle or elevated position, (indicated by dotted lines in Fig. 1,) in which position it will be observed that the counterweight (ball 15) assumes by gravity a position in the outer end of the casing 12, the weight of this ball and its distance from the pivot-rod being such as to slightly more than counterbalanee the weight of the stairway. When a person desires to descend from the platform 4 by means of the pivoted stairway, he simply steps from the platform onto the top step of the stairway, which step, it will be noticed, is so close to the fulcrum-rod that the effect of his weight will be to very slowly overbalance and elevate the counterweight and its containingcasing, and thus cause the outer free end of the stairway to gradually descend to the ground, after which the person may easily and quickly descend in safety. By the time the free end of the stairway is upon the ground the counterweight will have rolled from the outer to the inner end of its casing and will occupy the position shown in Fig. 1 in connection with the full-line illustration of the mechanism, in which position the weight of the stairway will slightly overbalance that of the counterweight, thus causing the stairway to remain in its lowered position. A subsequent slight lift of the free end of the stairway will start the ball again rolling toward the outer end of its casing, during which the ball will reach and pass the point of exact counterbalance between the weight and the stairway and will then of itself serve to complete the elevation of the stairway and hold the same elevated.

It will be evident from the foregoing that the employment of a loose connection between the counterweight-casing and the stairway and the provision of means such as the extensions 10 and stirrup l1 are not absolutely essential to the carrying out of my invention, since the casing 12 might be made rigid with the side members of the stairway; but I prefer the construction shown, for the reason that it is more convenient and economical to construct the stairway itself and the means for counterbalancing the same in separate parts.

The formation of the track or way 111 on which the counterweight rolls on a downwardly curved or dipped line, instead of on a straight line, secures a much more gradual travel of the counterweight from end to end of its casing, and thus insures a more gradual rising-and-falling movement of the stairway. This latter is of large importance, especially in connection with the descending movement of the stairway, since a sudden and jerky drop of the stairway would inevitably be attended by the danger of pitching headlong the person attempting to descend the same. It is sometimes found desirable to effect a slight vertical adjustment of the outer portion of the track on which the ball rolls in order to secure the most perfect balance of the parts and the most gradual and uniform movement of the stairway. To this end I may provide the stirrup 11 with a pair of adjusting-screws 16, whose manner of operation to effect this result is obvious.

Within the scope of the generically-novel mechanical features of the above-described device my invention is not limited to the specitic details of construction or relative arrangement of the parts herein shown, since it is obvious that the same might be considerably modiiied by the substitution of mechanical equivalents without departing from the spirit of my invention.

I claim- 1. In a device of the character described, the combination with the platform of a stationary Iire-escape, of a stairway pivoted at its upper end beneath the platform, a downwardly curved or dipped track or way rigidly connected with saidstairway and extending rearwardly of its pivotal axis, and a counterweight adapted to move to and fro over said track or way in the operations of raising and lowering the stairway, substantially as described.

2. In a device of the character described, the combination with the platform of a stationary iireescape, of a stairway pivoted at its upper end beneath the platform, a casing connected with said stairway in rear of its pivotal axis, a downwardly curved or dipped track or way in said casing, and a ball-counterweight adapted to roll to and fro from end to end of said casing in the operations of raising and lowering the stairway, substantially as described.

3. In a device of the character described, the combination with the lower balcony of a stationary iire-escape and a pivot-rod iixed therebeneath, of a stairway pivoted at its upper end on said rod and having its side frame members extended beyond the pivotal point, a casing pivoted at its inner end upon said pivot-rod and at its outer part supported by and between said extensions of the stairway, a downwardly curved or dipped track in said casing, and a ball-counterweight adapted to roll to and fro from end to end of said casing in the operations of raising and lowering the stairway, substantially as described.

1.1.. In a device of the character described, the combination with the lower balcony of a stationary fire-escape and a pivot-rod fixed therebeneath, of a stairway pivoted at its upper end on said rod and having its side frame IOO IIO

mese l s members extended beyond the pivotal point, from end to end of said casing in the operaa stirrup hung transversely between and across the outer ends of said extensions, a casing 'pivoted at its innerl end upon said pivot-rod and at its outer part seated in and supported by said stirrup, a downwardly Vitnesses:

curved or dipped track in said casing, and a SAMUEL N. POND, bali-counterweight adapted to roll to and fro FREDERICK C. GOODWIN.

substantially as described.

MICHAEL CODY.

tions of raising and lowering the stairway, Io I

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