Improvements in Fire Escapes.
Year: 1893

page_text: Date of Application, 3rd Mar., 1893-Accepted, 15th July, 1893
Improvements in Fire Escapes.
I, JOHN FRANCIS SHAW, of 53 Perine Street, Auburn, in the County of
Cayuga, and State of New York, Moulder, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
My invention relates to fire escapes whereby persons may be safely lowered to
the ground from buildings and other places, and its object is to provide certain
improved means for enabling descents to be made at a moderate speed, to prevent
casualties, with provisions for stopping the journey downwards at any point desired
with ease and facility. Further my improvements consist in the simple and cheap
construction of the apparatus in which the parts are made easily adjustable for use,
and adapted to be all held together by a single bolt and nut.
In order that my invention may be properly understood I have hereunto annexed
a sheet of drawings on which similar letters of reference indicate corresponding
parts on all figures alike.
Figure 1 is a vertical transverse sectional view with the drum and rocking arm
and pin shown in full lines, and with the rope guide removed.
Fig. 2 is an inverted view of one of the side plates with wall of casing.
Fig. 3 is a similar view of the opposite side plate showing the bearing, recess,
and guides.
Fig. 4 is a plan view of the rocking arm.
Fig. 5 is a side elevation of the rope guide showing the passages in dotted lines,
the direction of one of the passages being indicated by arrows.
Fig. 6 is an end elevation of the same.
Fig. 7 is a central longitudinal section of the same.
Fig. 8 is a plan view showing the bevelled gear of the drum.
In the drawings A represents the casing employed with my apparatus, to contain
the working parts. This casing comprises a casting B preferably in the shape of a
horse shoe forming a wall and having the side plates CD. The plate C is per-
manently secured to the wall B, and has an inwardly projecting flange a formed at
its lower end and running crosswise between the two ends of the wall, the purpose
of which flange will be described hereinafter. The side plate D is provided around
its entire edge with the inwardly projecting flange b the lower portion of said
flange having the extension b', shown best in Fig. 1. The purpose of this flange
is to hold the plate in its proper position relative to the wall. The flanges a and b
are provided for the purpose of supporting what I please to term a rope guide and
friction brake E, said rope guide and friction brake having outwardly projecting
flanges c d forming hangers to engage with the flanges a and 6'.
The parts thus far described, forming the casing and rope guide, being assembled
together are held in position by a pin or bolt e which is passed centrally through
the casing, and secured by a nut f. The said bolt e also acts as a shaft upon which
a.drum F is rotatably mounted within the casing, the face g of said drum being
provided with a bevelled gear h, acting as a pinion and consisting of an uneven
number of V-shaped teeth for a purpose to be hereinafter described.
The side plate D has upon its inner surface an upwardly projecting portion i
forming a bearing for a rocking arm or double acting pawl G, a suitable recess j
being formed in the plate D to provide a suitable space in which the rocking
arm may be free to vibrate. Guides are also formed on the inner surface of the
plate D to prevent the rocking arm from rotating with the bevel gear h and drum F,

page_text: said guides also serving as a bearing to prevent the gear from coming in contact
with the plate D.
The rocking arm is formed of substantially oblong shape with a V-shaped
extension at either end forming pawls to engage with the V-shaped teeth of the
bevelled gear h. The rocking arm is somewhat hollowed out on its under side at m
forming a bearing surface adapting it to bear against and rock upon the bearing i.
The rocking arm is mounted upon the pin or shaft e and is so adjusted in relation
to the gear that a vibrating motion is imparted to said arm by the rotation of
the drum and gear.
The rope used with my escape is preferably wound twice upon the drum, suitable
ribs n being provided upon the inner surfaces of the drum plates forming a tension
to prevent the rope from slipping. The drum hub o is extended somewhat beyond
the drum plate p, forming a bearing to prevent friction between said plate and the
side plate C.
The rope guide or friction brake E is provided with passages q r of substantially
S-shape in central longitudinal section, the inlets and outlets of the two passages
being opposite to each other as shown best in Fig. 5 in dotted lines, this arrange-
ment enabling the rope to be crossed, whereby it is adapted for use as a friction
brake. In rigging my improved escape the end of the rope is passed through one
of the passages 9 r, thence around the drum (preferably twice) and returned
through the opposite passage in the guide, when either end of the rope may
be used.
If preferred an endless rope may be employed whereby either of the depending
parts can be employed at will.
I may use a hanger to support the apparatus, which hanger may be permanently
secured where required. A supporting bail for engagement with the hanger afore-
said is formed in two parts s t, each part being made integral with the side plates C
and D, the meeting ends of said parts st being halved and adapted to fit together
and appear as one piece.
Another advantage of my apparatus is that it may be utilized as a pulley by
simply removing the rocking arm, whereby the drum will be free to revolve upon
the shaft in the manner of a sheave turning within its block.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a fire escape a casing consisting of a substantially horse shoe shaped wall
having one side plate permanently secured thereto, the said side plate being
provided with an inwardly turned flange, also a separate side plate having an
inwardly turned flange around its end and adapted to fit loosely over and
close the open side of the wall, together with a rope guide and friction brake
having outwardly projecting flanges or hangers for engaging with the flanges on
the side plates to connect the rope guide with the casing, substantially as and for
the purpose described.
2. In a fire escape a casing adapted to contain the working parts the said casing
being composed of a wall and two side plates, together with a pin or bolt passed
centrally through the side plates and holding the parts together, the said pin also
acting as a shaft upon which is mounted the drum and rocking arm, substantially as
and for the purpose described.
3. In a fire escape a rope guide and friction brake provided with passages for the
rope of substantially S-shape in central longitudinal section, the inlets and outlets
of the said passages being opposite to each other, substantially as and for the
purpose described.
4. In a fire escape the combination with the casing containing the working
parts, of a supporting bail formed in two parts, one part of said bail being
attached to each of the separable parts of the casing, the said parts of bail being
each halved at their ends, and adapted to fit oue upon the other when the casing is

page_text: adjusted together with a pin or bolt passed centrally through the casing and
secured by a nut locking the parts of the casing together, substantially as and for
the purpose described.
5. The improvements in fire escapes, substantially as and for the purposes
hereinbefore described, set forth, and illustrated.
F. W. BARKER,
Applicant's Agent.