Escape device for use in multistoried buildings

An escape device for use in tall buildings wherein an endless ladder-type chain driven around a plurality of chain sprockets is mounted on a movable platform and lowered over the side of a building to enable escape to ground level from a burning building. The endless ladder chain is compactly stored when not in use in a housing which includes a pair of inclined rod-like support members by which the endless chain under the force of gravity is slidingly dispensed from the chain housing to the sprocket assembly.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an escape device provided on a roof of a 
multistoried or high-rise building, and more particularly to an escape 
device for use in saving lives in the event of an emergency, such as fire. 
2. Description of the Prior Art 
Recently, a considerable number of fires have occurred in multistoried or 
high-rise buildings. During the resulting emergency, and despite existing 
escape provisions in buildings, such as escape stairs, escape chutes, 
escape ladders and the like for saving lives of escapees, the lives of 
many people are jeopardized and in the worst case, the loss of lives 
results. Under the aforenoted circumstances, nevertheless, there is a 
tendency to increase the height of buildings, so that the conventional 
type escape devices can no longer ensure the safety of lives of people. 
Accordingly, many kinds of escape devices have been proposed to this end 
for multistoried buildings. However, these devices pose problems in the 
construction and handling of the escape device, and in the safe descent of 
escapees from a burning building. 
SUMMARY OF THE INVENTION 
The present invention is directed to avoiding the aforenoted shortcomings 
or problems experienced with the conventional type escape devices. 
It is accordingly an object of the present invention to provide an escape 
device for use in a multistoried or high-rise building, which device may 
save the lives of people with ease and in safety, by ensuring the safe 
descent of escapees. 
According to one aspect of the present invention, there is provided the 
escape device of the type described which comprises: first and second 
driving sprockets; third and fourth idle sprockets; a ladder type endless 
chain trained around the first and second driving sprockets, as well as 
the third and fourth idle sprockets; a ladder-type-endless-chain housing 
positioned between the first driving sprocket and the fourth idle sprocket 
but below the first and the fourth sprockets; and a chain-lift prime mover 
for driving the first and second driving sprockets in both the normal and 
reverse rotational directions; whereby, in the event of an emergency, the 
ladder type endless chain admitted in the housing may be suspended between 
the second driving sprocket and the third idle sprocket, due to the first 
and second driving sprockets being driven by the chain-lift prime mover, 
and then the ladder type endless chain may be continuously paid out to 
descend a looped chain-lift portion. 
According to a second aspect of the present invention, there is provided 
the escape device of the type described, wherein the device further 
includes at least two rod-type chain supporting members which are rigidly 
positioned above the endless chain housing but below the first and fourth 
sprockets, and inclined so as to allow the endless chain to slidingly move 
therealong by gravity thereof, and the ladder type endless chain is 
provided with projecting portions or ladder steps which are engageable 
with the rod type chain supporting members and positioned at a suitable 
spacing along the chain, so that the latter type endless chain may be paid 
out from or drawn into the housing along the chain supporting member. 
According to a third aspect of the present invention, there is provided the 
escape device of the type described, wherein a turning prime mover for 
turning the sprocket housing and the endless chain housing, a wheeled 
platform mounting the sprocket housing, the endless chain housing and the 
turning prime mover thereon, and another prime mover for transporting the 
wheeled platform are positioned below the sprocket housing which is 
provided with the chain-lift prime mover and the first, second, third and 
fourth sprockets.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring now to the drawings, wherein like reference numerals designate 
identical or corresponding parts throughout the several views, and more 
particularly to FIG. 1 thereof, the numeral 1 designates a ladder type 
endless chain, the numerals 2 and 3 designate third and fourth idle 
sprockets, respectively, and at 4 and 5 first and second driving sprockets 
are positioned between the third and the fourth idle sprockets, 
respectively. Shown at 6 is an endless-chain-lift prime mover which is 
positioned between the first and second driving sprockets and which drives 
the first and the second driving sprockets in both normal and reverse 
directions. 
The ladder type endless chain 1 is trained around the first, second, third, 
and fourth sprockets 4, 5, 2 and 3 respectively so as to drive the same at 
a given rotational speed. Preferably, cam clutches should be provided for 
the third and fourth idle sprockets so as to prevent the reverse 
travelling of the ladder type endless chain. Shown at 8 are cam followers 
which cope with a slack of the ladder type endless chain due to its 
gravity, and the cam followers 8 are positioned at a given spacing above 
the first and second driving sprockets 4 and 5 between the third and 
fourth idle sprockets 2 and 3. Shown at 9 is a sprocket housing which 
admits the first, second, third and fourth sprockets therein. 
Shown at 10 is a stopper means which is positioned between the second 
driving sprocket 5 and the third idle sprocket 2, and the stopper means 10 
serves to stop the ladder type endless chain, at the completion of the 
return of the ladder type endless chain into the sprocket housing 9. The 
stopper means 10 includes: a swingable arm 12 which is freely swingable 
about a fulcrum 11 positioned above the second driving sprocket 5; an 
auxiliary idle sprocket 13 mounted on one end portion of the swingable arm 
12 so as to prevent the ladder type endless chain from coming off the 
second driving sprocket 5; and a limit switch 14 adapted to automatically 
stop the chain-lift prime mover, when the swingable arm 12 contacts the 
switch 14, upon the completion of the return of the chain into the 
sprocket housing 9 due to the reverse rotation of the first and second 
driving sprockets 4, 5. Shown at 15 is a ladder type endless chain housing 
positioned between the first driving sprocket 4 and the fourth idle 
sprocket 3 but below the first and fourth sprockets 4 and 3. Shown at 16 
are at least two rod type chain supporting members which are positioned 
above the endless chain housing 15 but below the first and fourth 
sprockets 4 and 3, and inclined so as to allow the endless chain to 
slidingly move therealong by gravity thereof. The ladder type endless 
chain is formed with a projecting portion, (in this embodiment, the 
projecting portions are ladder steps 23), which engages the rod type chain 
supporting member 16, so that the endless chain may properly be placed in 
the endless chain housing in suspended relation from the rod type chain 
supporting members 16 in order. 
Shown at 17 is a turning prime mover which is positioned below the sprocket 
housing 9 and drives the sprocket housing 9 and endless chain housing 15 
so as to turn through an angle of 90.degree. to the right and left, 
respectively, as viewed from the front of a building. Shown at 19 is a 
wheeled platform or board which mounts thereon the sprocket housing, 
endless chain housing and turning prime mover, while the platform 19 is 
capable of running along rails. Shown at 20 is a platform-travelling prime 
mover for driving the wheeled platform to travel along the wall of a 
building. Shown at 21 are rails for guiding the wheeled platform 19 in 
parallel with the wall of a building on the roof thereof. Meanwhile, shown 
at 23 and 24 are ladder steps and chain links of the ladder type endless 
chain 1, respectively. Shown at 25 are reduction gear mechanisms, such as 
a worm reduction gear mechanisms, mounted on prime movers 6, 17, 20, 
respectively. 
The operation of the escape device according to the invention provided on a 
roof of a multistoried or high-rised building is now described. In an 
emergency where fire for instance occurs on a certain story of a 
multistoried building, the platform-travelling prime mover 20 is first 
driven so as to move the wheeled platform 19 mounting the escape device 
according to the invention thereon, along the rails 21, to a position 
which allows safe escape of people from the story where an emergency has 
taken place, or escape of people from the stores above a burning story. 
Then the turning prime mover 17 is driven so as to turn the sprocket 
housing 9 and endless chain housing 15 through an angle of 90.degree. to 
the right or to the left through the medium of the turning gear 18, 
thereby bringing the second driving sprocket 5 and third idle sprocket 2 
outside of the fence 22 of a building. Then, the chain-lift prime mover 6 
is driven. As a result, the first driving sprocket 4 and second driving 
sprocket 5 are driven through the medium of a power transmission 7, so 
that the ladder type endless chain 1 which has been admitted in suspended 
relation from the rod type supporting members 16 inside the endless chain 
housing 15 may be suspended between the second drive sprocket 5 and the 
third idle sprocket 2 along first driving sprocket 4 and second driving 
sprocket 5 therealong. Subsequently, the ladder type endless chain 1 
trained around the first and second driving sprockets 4, 5 as well as 
around the third and fourth idle sprockets 2, 3 is continuously operated 
at a given speed so as to allow an escapee to descend in safety. After the 
escape device according to the invention has been operated completely, the 
escapees are transferred from a window, an emergency door and the like to 
the ladder type endless chain 1 one after another, with their hands and 
feet gripping and placed on the ladder steps 23 of the ladder type endless 
chain 1, respectively. 
In this manner, people to be rescued may reach the ground in safety, 
quickly, only by gripping by their hands and placing their feet on the 
ladder steps 23 of the ladder type endless chain 1. 
It is noted that in the aforenoted operation, the order of driving the 
driving prime mover 20 and turning prime mover 17 should not be construed 
in a limitative sense, so that either one of these may be driven first, or 
both of them may be driven at the same time. As the case may be, the 
escape device according to the invention may be operated in its set-up 
position, without driving the platform-travelling prime mover 20. 
Furthermore, it is preferable that the ladder type endless chain 1 be 
suspended to a position spaced such a distance from the ground, that 
ensures safe escape for escapees. In addition, although not shown, an 
endless chain fixing base equipped with an idle sprocket may be set up on 
the ground for preventing the lateral swinging of the endless chain due to 
wind, during the service of the escape device. Still furthermore, it is 
preferable that a water and wind proof cover be provided in a manner to 
enclose the chain-lift prime mover 6 and power transmitting means 7, and 
the like, therewith. 
The escape device for use in a multistoried building according to the 
present invention in such that the escape device on the wheeled platform 
19 may travel along the rails 21 in parallel with the wall surface of a 
building. Alternatively, however, the rails 21 may be of a movable type in 
a manner to assume the direction at a right angle to the wall of the 
building, so that the wheeled platform 19 may travel back and fourth 
perpendicularly to the wall surface of a building. Still furthermore, the 
escape device may be rigidly fixed in position, with the rails 21, and 
platform-travelling prime mover 20 being removed. However, in this case, 
the operational position of the escape device, i.e., the position in which 
the ladder type endless chain 1 is suspended with the second driving 
sprocket 5 and third idle sprocket 2 placed in the sprocket housing 9 
being brought outside of the fence 22 of a building, should be suitably 
fixed. However, in the event of raging fire right under the position of 
the escape device, when the escape device is thusly fixed thereabove, 
there arises a failure to ensure the safe escape or descending of people 
from a building. For this reason, the escape device should preferably run 
in parallel with the wall surface of a building. 
Meanwhile, in the event of fire, electric power may possibly be cut off. 
Accordingly, an emergency power source for driving the prime moves 6, 17, 
20, not necessarily limited to an electric power source, but an emergency 
power generator such as a diesel generator should preferably be provided. 
In addition, controlling and operating devices for these emergency power 
generators may be positioned on the roof of a building, but preferably in 
a control room, or in a suitable position on the first floor of a 
building. 
It is noted that the length of the ladder type endless chain 1 in the 
escape device according to the invention is governed by the height of a 
building, in which the escape device is to be placed. In addition, the 
number of escapees who can be carried on the ladder type endless chain 1 
at a time is dependent on the type of material, strength and weight or the 
maximum allowable load of the endless chain 1. Furthermore, the allowable 
safe descending speed of the ladder type endless chain 1, the running 
speed of the sprocket housing 9, and travelling speed of the wheeled 
platform 19 are governed by the prime movers 6, 17, 20 and reduction gear 
mechanisms 25 such as worm reduction gear mechanisms to be mounted on the 
prime movers 6,17, 20. Accordingly, the aforenoted factors should be 
determined, taking into considerations the capacity of a building, in 
which the escape device according to the invention is to be placed. 
As is apparent from the foregoing description of the escape device for use 
in a multisotried building according to the present invention, even if an 
emergency such as fire occurs, the chain-lift prime mover is driven so as 
to continuously operate the ladder type endless chain trained around the 
first and second driving sprockets, as well as around the third and fourth 
idle sprockets at a travelling speed within a range of a safe descending 
speed, so that escaping people may be transferred to the ladder type 
endless chain with ease and in safety from any position of a building. In 
this respect, the escapees should only grip by hands and place their legs 
on the ladder steps of the endless chain, when transferred from the 
building to the endless chain. In addition, a driving energy source may be 
remote-controlled. Yet furthermore, the provision of the endless chain 
housing enables compact storage of the chain inside the housing, with the 
aid of the rod type chain supporting member. In addition, the driving and 
idle sprockets in the escape device may be brought outside of the fence of 
a building, and the device may be movable in parallel with the wall 
surface of a building, thereby ensuring desired safety and compactness in 
size. 
Obviously, numerous modifications and variations of the present invention 
are possible in light of the above teachings. It is therefore to be 
understood that within the scope of the appended claims, the invention may 
be practiced otherwise than as specifically described herein.