Improvements in Automatic Fire Traps for Elevator Shafts.
Year: 1894

page_text: Date of Application, 6th Feb., 1894-Accepted, 7th Apr., 1894
COMPLETE SPECIFICATION.
Improvements in Automatic Fire Traps for Elevator Shafts.
We, THOMAS GAYLORD LAMB, of Homestead, Pennsylvania, Inventor, and
GEORGE FRANCIS PITTS, of Duquesne, Pennsylvania, Real Estate Agent, 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:-
Our invention relates to improvements in automatic fire traps for elevator:
shafts and it consists in the particular arrangement and construction of parts which!
will be fully described hereinafter and particularly pointed out in the claims.
The object of our invention is to provide an elevator shaft with doors above and
below the elevator car, which as the car ascends takes with it the doors above it,
and leaves the doors beneath it at the different landings, and when the car descends
the doors above are left one at each landing, whereby the shaft is kept closed at
all times against the draught which draws the flames thereinto; and to provide
yielding stops for the doors whereby all noise by them is prevented as the car
passes up and down its shaft.
In the accompanying drawings ;
:
Fig. 1 is a sectional view of an elevator shaft and car, with our invention applied.
thereto, the car being shown at the top of the shaft.
Fig. 2 is a similar view with the car at the bottom of the shaft.
Fig. 3 is a perspective of a series of lower floors showing the supporting chains
attached thereto, the safety guide-rail, and the stops.
:
Fig. 4 is a vertical section of an elevator shaft and car showing a modified form
of arranging the supporting chains for the lower doors.
Fig. 5 is a detached plan view of one of the doors.
Fig. 6 is a similar view of a door for a triangular elevator shaft.
Fig. 7 is a sectional view looking down on one of the yielding stops.
Fig. 8 is a vertical sectional view showing one of the yielding stops.
Fig. 9 is an enlarged view of a portion of one of the doors showing the safety
guide-rail.
Figs. 10 are detached views of the upper doors.
Figs. 11 are similar views of the lower doors.
Fig. 12 is a detached enlarged view of one of the weights.
;
A represents an elevator shaft of any desired construction, and B the several'
floors of the building in which it is placed. C is a series of upper doors which
are carried on top. of the car as it ascends and which follow it as it descends, each*
succeeding door beginning with the upper one being stopped and supported at the
floors as the car descends. The automatic stopping of these doors successively as the
car descends is accomplished by providing a series of stops e projecting from opposite
sides of the walls of the shaft, out of a vertical line one with the other and by
providing each succeeding door after the top one with slots F in their edges which
are made widest in the lower door to permit it to pass the upper stops and narrowed.
in the door next above and so on, thus causing each succeeding door to engage the
proper set of stops to support it at the proper floor as the car descends as will be.
readily understood.
D is a series of doors below the car, and to opposite sides or corners of'
these doors chains a, are attached, the opposite ends of these chains being attached
to the weights b, at the centre of the adjacent wall of the elevator shaft.
Attention is directed to the fact that the two chains a, at one end of the door.
$

page_text: pass up the shaft and over two pulleys d, and thence inward and downward to
opposite sides of a single weight, the weights having projecting arms for that
purpose. Owing to this construction each end or side of each lower door is
supported by a single weight and from two corners. The advantage of this
construction is that when one portion of the door binds from any cause, the
chain attached to the unbound portion is slackened, and this places the whole
of the upper pull of the weight attached to the two chains, upon the binding
portion, which will be sufficient to cause it to move upward evenly behind the
ascending car. It will also be noticed that the projecting arms of each succeeding
weight below the top one are made slightly longer than the arms of the weight
above, so that the chains extending upward from the weight below are clear from
the arms and chains from the weight above, and that the two pulleys at the top of
the shaft over which the chains pass are placed one series above the other, and
each succeeding series beginning with the lower are slightly farther apart so that
the chains for the upper pulleys are outside of the chains of the lower series of
pulleys.
Owing to this construction we are enabled to place all of the weights at each
side of the shaft in a single slide-way, each weight taking only about one inch
more space horizontally than the weight above, so that when the invention is
applied to buildings having say twenty floors there is only an increase of twenty
inches of horizontal space over that required for a single floor building. A marked
advantage is gained by this when compared with the usual method of placing the
weights side by side and providing a separate weight for each corner or chain of
each floor, thus requiring forty chains and forty weights side by side, making such
a construction impractical as applied to high buildings if not impossible of application
thereto.
As the car descends each floor remains in its place closing the shaft at that point
until the car reaches it and carries it down, thus entirely shutting all draught from
one floor of the building to the one above or below no matter at what point of the
building the car may be.
The pulleys d, are placed with their face or sides to the wall of the shaft, which
enables us to apply our invention to an ordinary shaft, putting the pulleys in the
space ordinarily left between the car and the walls of the shaft, whereas if the
pulleys were placed edgewise to the wall, a special shafting must be provided to
accommodate them.
Referring now to Figs. 7 and 8, it will be seen that the stops upon and against
which the upper and lower doors abut, consist of outwardly extending lugs e, which
have at their inner ends projections f, both of which slide in suitable castings
placed in an opening between a floor and ceiling of each story of the building, and
that these stops are provided with springs above and below them, so that the upper
and lower doors are received upon yielding stops, which makes substantially a
noiseless arrangement, that is very desirable. In fact we deem it almost indis-
pensable for passengers would be frightened by the noise otherwise occasioned as
the car moved up and down the shaft.
If thought necessary springs h, of any desirable construction, or cushions,
may be placed upon the corners of the adjacent faces of the upper and lower
doors, so that as they come together, the noise will also be prevented and lessened
thereby.
Each door is provided with plates m having recesses n, which receive the
lateral flanges of the safety guide-rails i. If these rails were not provided, the
upper doors would be liable to bind and turn edgewise and descend headlong upon
and through the top of the car. By providing the guide-rails, however, all
possibility of such an occurrence is entirely avoided, and the doors compelled to
descend evenly.
It will of course be understood that the weights for the lower doors are sufficient
to overcome their weight so that they are automatically raised behind the car as it
ascends. So also the lower doors are stopped in the same manner as the upper

page_text: doors, by having the slots at their edges increased in width from the lower to the
upper one as clearly shown in Figure 11.
In Figure 4 we show a modified form of arrangement of the pulleys for the
chains, in which event we have the pulleys s, arranged below each floor in succession,
instead of arranging all of them at the top, whereby a great multiplication of the
chains at the corners of the shaft throughout the entire length thereof is avoided
as clearly illustrated.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
--
1. The combination with an elevator shaft and car, a series of vertically moving
horizontal doors, two supporting connections at each side or end of each door, and
a single weight for each two connections.
2. The combination with an elevator shaft and car, of a series of vertically moving
horizontal doors, a single weight for each end or side of each door, the weights
at one end or side being in a vertical line one above the other, and connections
between the ends or sides of the doors and the weights.
3. The combination with an elevator shaft and car of a series of vertically
moving horizontal doors, a chain for each corner of the doors, two pulleys at the
upper end of the shaft for each chain, and weights which are connected to the ends
of the chains.
4. The combination with an elevator shaft and car, of a series of vertically
moving horizontal doors, a chain for each corner of each door extending upward
therefrom and across inward towards the centre of the shaft, and a single weight
for two of said chains at each end of the doors, to which the opposite ends of the
chains are connected at each side thereof.
5. The combination with an elevator shaft and car, of a series of vertically
moving horizontal doors, a single weight for each side of each door, the weights
being placed in a vertical line one above the other, a chain for each corner of each
door which extends upward and downward to opposite sides of their respective
weights the connecting points of each weight being wider than the connecting
point of the weight above, whereby the upper weights travel between the chains
attached to the lower weights.
6. The combination with an elevator shaft and car, of a series of doors above
and below the car, and a series of yielding stops for the doors.
7. The combination with an elevator shaft and car, of a series of doors moving
vertically with the door, and a series of spring supported stops which project into
the shaft.
Suait.
Dated this 6th day of February 1894.
For the Applicant,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.