US914661A - Fire-escape. - Google Patents

Description

Gj. H. JOHNSON.

' FIRE ESOAPB. 'Arrmourou uns AUG. 24.1909.

914,661 atented Mar, 9, 1909.

GEORGE HENRY JOHNSON, OF CHICAGO, ILLINOIS.

FIRE-ESCAPE.

Specification of Letters latent.

Patented March 9', 190e.

Appucation fuea August 24, 190s. serial Nemesis.

To all whom 'it may concern:

Be it known that I, GEORGE HENRY. J onnl SON, a citizen of the United States, residing at Chicago, county of Cook, and'State of Illinois, have invented veertain'new. and useful Im rovements in Fire-Escapes, ofv which the fol owing is a specilication.

My invention relates to lire-escapes and has particular reference to lire-escapes havingv a swinging and counterbalanoed lower llight of steps. I

The object of my invention is to rovide a ire escape equipped with im rove means for regulating or governing t e downward swing of tl steps to avoid undue shock when they reach the bottom or lowermost position. l

` Other objects will appear hereinafter.

My invention will be morereadily understood by reference to the accompanying drawings forming a part of' this spe'cilication and in which- Figure 1, is a side elevation ofa portion olf' a lire escape equipped with the governor embodying my invention in its preferred form, and Fig. 2, is a detail elevation of the governor'. Fig. 3 is a longitudinal section thereof taken on the line X-X of Fig. 41.

Referring to the drawings, 1 indicates 4the lower landing of the lire-escape having the rails 3 and 4 forming a passageway tothe lower flight of steps. The lower ligt usually comprises the stationary upper ortion 5 and the pivoted lower portion 6. i he' side members 7 of the lower portion are pivotally connected asat 8 to the side members of the upper portion 5, and the outer side member 7 is extended beyond the pivot as indicated at 9 and provided with the counterbalance weights 10.

As soon as a person steps upon the upper step of the flight the flight begins to descend, at first slowly, but increasing with each succeeding step. To )revent too sudden descent ofthe flight an" an undue shock or jar when it reaches its lowermost position, I provide a governor. This comprises the weight 2O pivotally mounted as at21 in a bracket 22 secured' to the extension 9.

I am aware that wei hts have been rigidly fixed to the swingingjiight of stairs of a iireescape which act as a counterbalance. weights usually have their greatest leverage, and hence retard the drop of the steps when they lirst begin to descend more than they do toward the end oi. the drop. Further Suchl when the greatest leverage of such weight. is exerted, the lweight of the person exerts the least leverage lin as much as they are then closer to the pivotal point, and as the lever-l age due to the weight of the erson mereases,

the leverage due to the weig t decreases permitting a shock or jar whenthe flight reaches its lowermost position. "L counteract this inequality by pivotally mounting a pendulous weight so that the leverage due to the weight is rapidly decreased at first owing to the' center of gravity of the weight swinging toward the pivot point, and then as the leverage due to the weight of the personfis materially increased by the person advancing further from the pivot point arresting its inward swing and throwing its center of gravity outwardly in the opposite 4direction rom its pivot point and the pivot point of the flight.

The bracket 22 comprises a base liange 23 by which it is secured to the member 9, the vertical portion 24, the oilsetportion 25 and the de ending portion 26. The weight -is pivote betweenrthe vertical portions 24 and 26 and is provided on the side adjacent to the pivot 8 with an ear or lug 27 which engages the offset portion 25 after the steps have swung downwardly a short distance, 1n practice about 20 or 30`degrees. This causes Y the weight to be raised or swung outwardly from this pivot in the opposite direction from the advancing weight on the stairs 6, which counteracts the increasing leverage of the person on the ste s. It is obvious that the device may. e arranged upon any lire-escape charac erized by a counterbalanced lower flight of steps and that ,at little cost and without vchange or alteration to the rire-escape.v y

Having described my invention what I claim as new and desire to secure by Letters Patent is: n

1. In a fire-escape the lower landing in combination with the lower llight of steps hingedly connected thereto, a weight pivotally secured to said steps .and ada ted to swing toward the pivota during the first portion of the downward swing thereof and means adapted to arrest the inward swing of said weight during the remainder ofthe downward movement, substantially as described.

2. In a fire-escape the lower landing in combination with the vlower 'flieht of steps hingedly connected thereto, sairl flight havpoint of t e steps ing a rearward extension beyond its^`pivota1 point, a bracket secured to said extension and a depending weight pivotally connected 'to said bracket,- said welght being adapted 5 to swing inwardly during the first portion of the "downward swing of the steps and coacting means on said weight and said bracket for arresting the inward swing of the weight during the remainder of .the downward swing 10 and causing the'same to swing outwardly in ,I

the opposite direction from the steps, :substantially asv described.

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

GEORGE HENRY JOHNSON.

Witnesses g* i A NNA L. EKVALL, JANET HOGAN.

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