Improvements in and relating to Means for Closing and Fastening and Unfastening Railway Carriage Doors.
Year: 1892

page_text: Date of Application, 12th Dec., 1892-Accepted, 27th May, 1893
CUMI LEIM DIECIFICATION.
Improvements in and relating to Means for Closing and Fastening
and Unfastening Railway Carriage Doors.
I, RODERICK NICHOLSON MONTGOMERY, of Salisbury Buildings, Bourke
Street, Melbourne, in the Colony of Victoria, Gentleman, 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 :-
The subject matter of this invention is similar to that for which I obtained
British Letters Patent No. 3886 and dated the Fifth day of March One thousand
eight hundred and eighty-nine.
The objects of this invention are 1st to provide means whereby the engine driver
or other authorised official can safely and without risk to passengers close and
fasten or unfasten all the doors of a train from the locomotive. 2nd, to prevent
doors being opened accidentally or otherwise, and insecure doors flying open while
a train is in motion. 3rd, to do away with the present dangerous practice of
ruuning trains with the doors on one side locked. 4th, to secure the comfort of
passengers by preventing the slamming of doors, and 5th, to enable passenger
traffic to be conducted with greater facility and less station labor than at present.
According to my invention, I provide an air compressor and reservoir upon the
locomotive or other convenient part of the train, and I connect said reservoir up to
a three-way valve, whereby the engine driver or other authorised official can place
said reservoir in communication with a door pipe extending from end to end of the
train or can cut off communication with said door pipe, or can put this pipe into
communication with the atmosphere so as to reduce the pressure therein. The
three-way valve, hereinbefore mentioned, has a small port or opening which is
provided for the purpose of supplying compressed air or other motive fluid to the
carriage door pipe to replenish the supply of fluid in case of any escape from said
door pipe through leakage or otherwise during running. The flow of fluid in
passing through this opening from the reservoir to the carriage door pipe travels
through a chamber in which is seated a reducing valve. The object of having
this resisting or reducing valve is that there may be a higher reserve air pressure
in the reservoir at the command of the operator than in the carriage door pipe
before mentioned.
The handle of the three-way valve may have an ordinary spring stop and two
sockets. The stop to be in one of these sockets whilst running with fastened
doors, and in the other socket whilst the train is standing at a station with
unfastened doors.
The act of catching the handle of the three-way valve tightly withdraws the
spring stop from the socket, and by reducing the pressure on the handle the stop
enters the desired socket when brought in line. Branches are led from the
carriage door pipe before mentioned up to an automatic valve whereby a cylinder
upon some convenient part of the carriage is automatically placed in communica-
tion with the atmosphere when the pressure in the door pipe is suddenly (however
slightly) reduced.
The object of this automatic discharge valve is to economise the fluid in the
door pipe when said fluid is to be discharged from the carriage door cylinder, and to
ensure that the pressure in the carriage door cylinder, and therefore on the doors,
is withdrawn when air is discharged suddenly from the carriage door pipe. The
before-mentioned cylinder is fitted with a piston and rod or the like connected
direct or otherwise with the door sliding rod having branches so as to close and
fasten the doors when the pressure is transmitted along the door pipe as described.
This door cylinder contains a spiral spring to return the piston to its normal

page_text: position when the air pressure is withdrawn. The door sliding rod having
branches, above mentioned and described and claimed in the Specification of my
former Letters Patent above referred to, is arranged to slide longitudinally upon
the carriage and works between or over anti-friction rollers, and allows the
passengers to open and close the doors freely when said doors are unfastened, as,
for instance, when a train is standing at a platform. An operating pivoted lever
across the carriage connects the sliding rod having branches upon the right side
with the sliding rod having branches on the left side of carriages by links. The
branches already referred to are connected with an arm projecting from a spindle,
mounted in brackets fixed to the carriages, having another arm attached or
connected to the door of the carriage. The door arm of the said spindle may
have an oblong slot formed in it to enable a small spring sliding bolt fitted in the
door to project into engagement with it. This oblong slot is shaped thus so that
the movement of the said spindle in the brackets need not necessarily be true to
the door hinge movement. In order to allow said doors to be closed after the
closing gear has been moved into its fastening position, stop pieces are arranged
upon the sliding rod, having branches above referred to, and are arranged to allow
the doors to pass them when being closed, but not when being opened. That is,
when the apparatus has drawn a door to within about an inch of the closed point,
the door becomes securely fastened and it cannot be pushed back again until the
air pressure has been withdrawn from the cylinder without disconnecting.
It would be very dangerous to passengers to so fit the stop catch that it could
not secure the door till it has been fully closed, because doors often "catch"
articles, such for instance, as the fold of a dress or a piece of paper which are not
noticed by passengers and the door would not be fastened, and any one who might
lean against it, believing the door to be fully secured, would be very likely to fall
from the train, as the door in such a case would give to very slight pressure. To
guard against this class of accidents I arrange the stop piece to act on the door
direct, or otherwise in such a way that when the air pressure has been put on the
piston and caused the sliding rod having branches to move to its full extent, the
stop pieces secure all the doors that are within about one inch of the closed point,
and any door which may have been held back and prevented from closing with the
others, will, so soon as allowed to come within about one inch of the closed point,
be at once secured by its own stop piece. This stop piece may be constructed in
different ways to produce the desired result, as can be easily understood when
the object for which it is provided is remembered, viz., to safely secure railway
carriage doors, although they may not have been fully closed, and to safely secure
any door which may have been kept open and prevented from closing with the
others, as described, so soon as said door has been allowed to get within about one
inch of the closed point.
I employ a spiral spring in place of the weight described and illustrated in my
former Specification on the flexible branches already mentioned. The effect of
this spring is that when anything is "caught" by a closing door it expands till
the obstruction has been removed, and then the door closes immediately. A
closing door can be held almost wide open by obstructing its travel without exerting
as much pressure as would injure a child, and the fact of one or more doors being
obstructed would not affect the travel or fastening of the other doors.
The small spring sliding bolt before mentioned is provided so that any door may
be disconnected when required for special ticket collecting, or for any other purpose
by railway officials, or by passengers in case of absolute necessity, as for instance:
when it is desired to throw a door open while a train is travelling, so as to draw
the attention of the guard or driver in order to stop the train, also so that the doors
may be opened by passengers in the event of the rods through unforeseen circum-
stances not releasing the doors during an accident to a train. Hitherto trains run
frequently with all the doors on one side key-locked, and in the event of an accident
and a portion of a train falling upon the side on which the doors are unlocked,
passengers have to leave the carriages through the window, and every one who

page_text: cannot do so has to remain in the carriage until released. The handle of this bolt
is fixed well up on doors or else placed near the bottom outside, so that passengers
will not disconnect and open doors near a platform without being seen by the station
officials.
To the guard's van I attach a main pipe with pressure gauge and a reducing cock,
so that the guard may know the strength of the pressure in the door pipe, and when
desired be able to unfasten all the doors by opening said reducing cock and allowing
some compressed air to escape into the atmosphere.
Referring to the accompanying drawings-
Figure 1 is a side elevation of a locomotive and carriage fitted with my
improved means for closing and fastening and unfastening the doors of said carriage
whilst
Figure 2 is a plan of said locomotive and carriage.
Figure 3 is a diagrammatic elevation showing the air compressor, steam valve,
reservoir and three-way valve above referred to as fitted by preference upon the
locomotives.
Figure 3 is a section of an automatic valve used for admitting steam into the
engine of the compressor.
Figure 3B is a similar view of a modification of said valve.
Figure 4 is a central horizontal section of said three-way valve, and
Figure 5 is a vertical section thereof on line 5, 5 Figure 4.
Figures 6 and 7 are sections of the automatic valve used for admitting the con-
pressed air from the main pipe into said door closing cylinder.
Figure 6 is a similar view of a modification of said valve.
Figure 8 is a longitudinal central section of one of the main operating or door
closing cylinders above referred to.
Figures 9, 10, 11 are respectively a side elevation, front elevation, and plan of
the anti-friction rollers used for supporting and guiding the operating rod, having
branches and which runs along the carriage.
Figures 12, 13 and 14 are details of the attachments upon the said rod to which
the flexible branches are secured.
Figures 15 to 18 are details of one of these rods illustrating the manner in which
the connecting levers are secured to it.
Figure 19 is a front elevation, and
Figure 20 a plan of a railway carriage door fitted with my invention, showing
said door in its closed and fastened position.
Figure 21 is a similar view to Figure 20, but showing the door open.
Figure 22 is a plan of the spiral spring and flexible connection used for con-
necting the main operating rod with each door.
Figure 23 is a side elevation, and
Figure 24 a plan of a catch which is fitted upon the operating rods to prevent a
fastened door from being opened beyond a certain extent.
Figure 25 is an end elevation of said catch.
Figures 26 and 27 are a plan and side elevation of a modified arrangement of
retaining catch, whilst
Figure 28 is an end elevation of said arrangement.
Figures 29 and 30 are elevations illustrating a sliding spring bolt used for con-
necting the door to the closing mechanism and which enables said door to be
readily disconnected therefrom should it be specially required to open it for any
purpose.
Figures 31 to 35 are diagrammatic plans illustrating a few modifications of my
invention.
Figure 36 is a plan,
Figure 37 a side elevation, and
Figure 38 an end elevation with the covers removed of an arrangement which I
sometimes use for returning the sliding rods having branches to their normal
nosition when the pressure is relieved in the main onerating cylinder.

page_text: Figure 39 is a side elevation of another arrangement which I use for this
purpose..
Figure 40 is a side elevation of a railway carriage showing one of the modifica-
tions of my invention fitted underneath the foot board.
Figure 41 is an end elevation of said carriage.
Figure 42 is a similar view to Figure 41 but illustrating another slight modi-
fication.
The same letters of reference indicate the same or corresponding parts in all the
figures.
A Figures 1, 2 and 3 represents the air compressor with steam engine attached
and which may be fixed in any convenient part of the locomotive, as illustrated in
Figures 1 and 2, and be operated by steam from the boiler.
The opening to the air suction valve is covered by gauze or wire cloth to prevent
as much as possible the entrance of foreign substances into the valves, as will be
well understood.
The supply of steam from the locomotive boiler is regulated by either of the
steam valves shown in Figure 3A and 3B, said valves being fitted upon the pipe
which connects the said boiler with the pump engine, so as to automatically regulate
the working of said pump to the requirements of the operator and to save labor.
The valve shown in Figure 3* is operated by steam and compressed air, and con-
sists of a case !, a steam chamber 2, a compressed air chamber 3, a sliding valve 4
and piston 5, connected by a rod 6. When the pressure in the air reservoir B,
(which is connected by a small tube 7 with the chamber 3, containing the piston 5,)
attains a given number of pounds to the square inch, the piston 5 and the rod 6
carrying the sliding valve 4, cause the flow of steam to the engine cylinder to be
reduced or cut off so as to reduce the flow of steam passing from the port 8 to the
port 9 or to entirely close said port 8 when the air pressure in the chamber 3,
acting on the piston 5, overcomes the steam pressure acting on the valve 4 in the
chamber 2, thereby reducing the speed of the engine and pump, or bringing them
to a state of rest. When the pressure in the reservoir B has been reduced by the
operator for door closing purposes or otherwise, the air pressure in the chamber 3
acted on by the piston 5 is overcome by the steam pressure acting on the valve 4
in the chamber 2, and a passage for steain to travel from the port 8 to the port 9 as
indicated by the arrows in Figure 34 is opened, thereby putting the engine and
pump again in motion to force air into the reservoir B, and so soon as the pressure
has been raised again the pump and engine are automatically stopped as already
described. This valve is very simple in its operation, and all its parts can be easily
and quickly separated and put together. In the modified form of valve shown in
Figure 3B, the pressure of air in the chamber 3 when it has risen sufficiently to
overcome the strength of the spring 10, turns the cock 4, so as to reduce or cut off
the flow of steam through the pipe 8 to the engine. The air compressor A, used
for forcing air into the reservoir B, may be constructed as preferred, and may be
fitted in any convenient position, such for instance, as upon the foot plate of the
locomotive as shown in Figures 1 and 2.
From the reservoir B a pipe & leads up to a three-way valve C whose construction
is clearly illustrated in Figures 3, 4, and 5.
From this valve a branch pipe e leads to the main door pipe D which extends
from end to end of the train, being coupled between the vehicles as illustrated at d,
Figures 1 and 2, by any suitable coupling. The casing of the valve C is formed
with three ports or passages el c² 3, and the plug e is formed with a port or
passage adapted to place either the port c' and in communication with each
other or the ports c¹ and c².
In addition to the port es, the plug e is provided with two small auxiliary ports c
and which serve, when the main communication (that is the port or passage c)
between the pipe 6 and the door pipe D is closed, to allow a small quantity of air
to pass through in order to supply the place of the air which may escape from the
pipes, and thus maintain the desired pressure therein. represents a small back

page_text: pressure valve which is inserted in the upper end of the auxiliary port c. The back
pressure on this valve c exerted by a small spring c is about 12 lbs., therefore
the pressure in the reservoir B must exceed that in the main door pipe D by more
than 12 lbs. to the square inch before air passes through the auxiliary ports cⓇ and c²
to the carriage door pipe for the purposes mentioned, as may be well understood.
62 represents a pressure gauge which enables the pressure in the reservoir B to be
noted by the engine driver or other person, whilst represents a pressure gauge to
enable the pressure in the door pipe D to be noted. e represents a small branch
pipe whereby the door pipe D may be placed in communication with a cylinder F,
fitted with a piston f, Figure 8, and a spiral return spring, this latter being
arranged around a piston rod 2 within an extension of said cylinder, as clearly
illustrated in Figure 8. A valve E, Figures 1, 2, 40, 41, and 42, is provided with
a plunger e, Figures 6 and 7, connected by a rigid connection e² with a sliding
piston e having a port e adapted to place the branch pipe e in communication with
a short length of pipe e leading to the operating cylinder F when said piston is in
the position illustrated in Figure 6. Should, however, the engine driver or other
official or through breakage of the door pipe D reduce the pressure in said pipe
suddenly, however slightly, and therefore in the branch e, the air contained within
the chamber e will act upon the plunger e', and will cause it to travel into the
position illustrated in Figure 7, when the pipe e leading to the cylinder F will be
placed in communication with the exhaust e', and communication with the main
pipe will be cut off. When the plunger el is in the position illustrated in Figure 6,
the passage e keeps the chamber e in communication with the cylinder F and the
door pipe D by means of the branch pipes e and e, so that while in this position
there is the same pressure in the cylinder F, the door pipe D, and in the chamber e
of the discharge valve, and by any sudden reduction of the pressure in the door
pipe D, as described, the air contained within the chamber e will act on the plunger
which will cut off communication between the chamber e and the passage e, as
illustrated in Figure 7, the end of the passage e being covered tightly by the back
of the plunger which is constructed to serve this purpose in order not to waste
the pressure in the door pipe D each time it is desired to empty the cylinder F.
When a carriage is disconnected with the intention of laying it up for an indefinite
period by unscrewing the plug e, the compressed air stored in the chamber e may
be released into the atmosphere, or by inserting the end of a wire into a passage
having a hinged valve in the chamber e, the air can be released simply as may be
well understood; however, it is not necessary to discharge the stored air from said
chamber to ensure the plunger and piston working properly afterwards, whatever
time the vehicle may lay idle, but the object is to relieve the plunger of a continued
unnecessary pressure.
I sometimes arrange a discharge valve worked as illustrated in Figure 6 by
means of two pistons e' e³ connected by a rod e having a link e to operate a
common plug containing the port e', opening e and part of the passage es. The air
in the chamber e serves to operate the plug of said valve and place the cylinder F
in communication with the atmosphere, and close the passage e leading through
the plug of the valve to said chainber, when the air in the door pipe and behind the
piston e is reduced suddenly, and it will keep them in this position until the air
pressure in the door pipe and behind the piston e³ has been raised by the operator,
when the pressure behind the piston e³ will overcome the pressure in the chamber e
and thus operate said plug so as to close communication between cylinder F and
the atmosphere, and open the passage es and the port e, thereby putting the
cylinder F and the chamber e in communication with the door pipe. Whilst in
this position the same pressure of air prevails in the carriage door pipe, in the
cylinder F, in the chamber e, and behind the piston e³. This valve is a modifi-
cation of the valve E, Figures 6 and 7, as may be well understood.
The piston rod fƒ2 Figures 1 and 2, is connected on to a lever G which is centered
upon the roof of the carriage or other convenient part and extends towards either
side thereof. Its ends are connected by links g to sliding rods H (having branches I)

page_text: which said rods extend longitudinally of the carriage, and work between or over
antifriction rollers & Figures 1, 2, 9, 10 and 11, supported upon brackets ¹ secured
to the roof or other convenient part of the carriage. The way in which the links g
are connected to the sliding rod H is clearly illustrated in Figures 15 to 18, said
sliding rods being provided with stirrup pieces 2, through one end of each of which
a bolt is passed, and serves as a pivot for the end of said connecting link G,
whilst the recess formed in said stirrup allows said link to work freely therein as
the lever G is moved. In suitable positions upon the sliding rods H are secured
brackets i constructed as illustrated in Figures 12 to 14 or otherwise. Through
these brackets are passed small bolts ', to which the ends of a spiral spring 2
Figures 1, 2, and 19 to 22 encircling or otherwise attached to a piece of chain,
cord, wire, or other flexible connection I is secured, said flexible connection being
sufficiently long to allow a certain amount of give to said spring as illustrated in
Figure 22. The opposite ends of these flexible connections I are secured to the
end of an arm J projecting from a short spindle j mounted in brackets j¹ fixed to
the side of the carriage, or to any other convenient part, as illustrated in Figures 1, 2,
19, 20, and 21 of the accompanying drawings. On the lower end of this spindle is
another projecting arm extending over, under, or behind the door K. Said arm
may have a slot ja Figure 20, formed in it to enable a small spring sliding bolt L
upon the door to project into engagement with it, said spring bolt being passed
through guides secured to the door in any convenient manner, and having a
spring so as to always keep it in its projected position as illustrated in Figure 19.
In order to secure the doors safely when the sliding rod H has been shifted to the
closed position, I secure stop pieces M upon the rod H for the purposes hereinbefore
stated.
If preferred, instead of connecting the cylinder F on to the lever G as illustrated
in Figures 1 and 2, it can be connected on to one of the sliding rods, and the
lever G merely serve to connect the two rods H, H, as illustrated Figures 31, 40
and 41, or if preferred said connecting lever G can be dispensed with as illustrated
in Figure 32, each rod being worked by a separate cylinder. The cylinder F can
be connected in various ways to the rods H, as will be well understood.
Instead of using the pivoted lever shown in Figures 1, 2, 31, 40, 41 and 42, a
straight cross bar can be used for connecting the two rods H, H as illustrated in
Figure 33, the flexible connection I on one side being in that case passed round
guide pullies 3.
Instead of placing the operating cylinder F on the roof or underneath the
carriage as illustrated in Figures 1, 2, and 40, 41 and 42, or close to where the
sliding rod H with its connections is placed, it can, if thought more convenient, be
arranged in some other part of the train, and a rope or other flexible connection f2,
Figure 35, can be led from the piston in said cylinder over suitable pulleys or
otherwise, in which case I prefer to use the arrangement illustrated in Figures 36, 37,
and 38, to return the sliding rod after the pressure has been let out of said operating
cylinders.
This said arrangement consists of a set of pulleys f mounted upon sliding
brackets f, and having springs f¹ fitted between them and a rigid cross piece f
within the outer containing case. Around these pulleys is passed a cord or other
flexible connection 6, whose end is secured to the cross bar G opposite to the
cord f, or else secured direct to the rod when the cord f2 and the sliding rod are
in line, that is when two cylinders are used for each carriage. It will be
obvious that as the pressure in the operating cylinder F is released that the
springs will force the pulleys 3 apart, and will thus cause the cord f to draw
the sliding rod H back into the normal position-that is so that the doors can be
opened.
The arrangement illustrated in Figures 26 to 28, for fastening the doors when
they are closed, consists of a pivoted counter-balanced catch M, centered upon a
bracket m secured to the carriage, and so arranged that when the sliding rod H is
moved into its fastening position, that is so as to close all the free doors, a cam

page_text: projection m¹ on it will ride over the end of said lever M, and will raise its opposite
end into the path of the arm J and will thus prevent the door from being opened,
by preventing said arm from being moved back.
The operation of my appliances for closing and fastening and unfastening
railway carriage doors is as follows:-Assuming that the engine-driver or other
official desires to close the doors of a train, it is merely necessary for him to turn
the three-way valve C into the position illustrated in Figure 5, when compressed
air from the reservoir B will pass along the pipe b and therefore the ports c³, c, cl
to the door pipe D, and from this along various branch pipes e on each carriage to
the valve E which will by such pressure be moved into the position illustrated in
Figure 6, so that there will be a clear passage from said branch pipe e through. the
port and short length of pipe e into the cylinder F, the piston f of which
will thus be forced forward and will keep the lever G in the position illustrated in
Figures 1 and 2, that is with the two sliding rods H in such a position as that they
cause the spiral springs and flexible connections I to exert a pull upon the arms .J
attached to the doors, which latter will thus be held in their closed position. They
can, however, be opened to a certain extent on turning the ordinary present handle,
by overcoming the tension of the spring 12, but will be prevented being opened too
far by the stop M, as before described. The driver only opens the valve C in the
manner just described for sufficient time to fill the cylinder F, door pipe D, and
branches e, with compressed air, and then turns said valve into such a position as to
bring the two ports e, c7 opposite the ports c¹, c³, when sufficient air will be free to
pass through into the door pipe D, to compensate for any slight leakage that might
take place through the joints or elsewhere.
When the engine-driver or other authorised official desires to unfasten the doors
of the train, it is merely necessary for him to turn the valve C round until the
passage in the plug opens communication between the port cl and the port c³, the
effect being to allow a certain quantity of air to escape into the atmosphere from
the door pipe and branches e, which will, as before described, allow the air contained
in the chamber es of the valve E by means of the plunger e', to overcome the
resistance of the opposite side of the piston e³, and thus force said plunger together
with the piston forward into the position illustrated in Figure 7, when the
cylinder F will be put in communication with the atmosphere by the exhaust e', and
thus the spiral springs f¹ will be enabled to return said piston in said cylinder as
well as the lever G and sliding rods H to their normal position, that is, so that they
will release the arms J, and thus allow the doors to be opened in the usual way.
Suppose the cylinder F to be 6 inches in diameter, the stroke of the piston to
be 6 inches, the door pipe D inch in diameter, that the invention is applied to a
train of 15 vehicles so that the capacity of the 15 cylinders is 1.472 cubic feet,
that the contents of door pipe and branches are say another 1.472 cubic feet, and
that 017 cubic feet are allowed to escape from the door pipe D to operate the
several valves E, then to close, fasten and release all the doors on the 15 vehicles,
about 1642 cubic feet of compressed air will be sufficient. This great economy
of air is brought about by the automatic discharge valve E, which effects the
saving above described. Another advantage is that in the event of an accident to
a train, the pressure escapes from the cylinder F, and thereby unfastens the doors
as described. A valve requiring an auxiliary reservoir for charging the said
cylinder is not at all suited for door controlling purposes, as in the event of an
accident to a train and the door pipe being damaged so as to allow air to escape,
full pressure would be maintained on the piston of the carriage cylinder if the
doors were closed by air pressure. If air. pressure is merely employed to keep
doors unfastened, and the cylinder became damaged in any way, the appliances
would prevent doors being opened.
The valve E does not require any auxiliary reservoir, and none should be added
for the reasons above stated. The air pressure on the piston of the cylinder F
cannot at any time be more than prevails in the carriage door pipe D, and any
sudden reduction in this pipe, as stated, will at once release the doors.

page_text: I sometimes attach an index pointer to the handle of the three-way valve anu
letter them thus :-
F--(fasten) which indicates the position the index pointer should occupy to
close and fasten, that is, said pointer should be in the vicinity of the letter F
when it is desired to close and fasten, and after the door pipe D has been 5
filled as already described said pointer is moved to-
R-(running) which shows this position before described, that is, with the
passages in position to allow air to flow from the pipe b to the door
pipe D to guard against accidental leakage, and when it is desired to dis-
charge air from the door pipe to unfasten doors as described the index
pointer is turned to-
D (discharge) for a few seconds, and then shifted to-
U-(unfastened) which indicates the position it should occupy when the doors
are unfastened and communication between the ports of the valve c cut off.
Because such a small quantity of power serves to close, fasten and unfasten the
doors of the train according to my invention, locomotives having an air compressor
for operating the brake blocks by compressed air can have the air necessary for
working the doors taken from this compressor and stored in a separate reservoir.
To arrange this so as not to endanger or interfere with the brake power, a valve,
such as that herein described, having a spring piston air chamber and a plug, may
be fitted on the pipe leading to the door reservoir. The spring must be strong
enough in proportion to the piston surface to keep the passage in the plug open
with a pressure of 25 lbs., that is, when the pressure in the door reservoir is raised
over 25 lbs. to the square inch the piston overcomes the spiral spring pressure, and
cuts off the flow of air to the door reservoir, and when the pressure in said reservoir
becomes less than 25 lbs. to the square inch the spiral spring opens the valve for
air to flow, and thereby re-charge the door reservoir. A pressure of 25 lbs., or
even less, in the door reservoir is sufficient for the purpose of closing the doors
of railway carriages.
When the hose couplings between the vehicles constituting the train have been
united and the locomotive door coupling connected with the train, the cock at each
end of the train is shut off, that is, the cock on the door pipe at the tail end of the
tail vehicle and the cock on the forward end of the locomotive are closed, but all
the other cocks on the door pipe D and cylinder branch pipes e throughout the
train must be open. Should any of the cylinders F be damaged in any way, the
stop cock on the branch pipe e of the injured cylinder is of course closed, otherwise
the pressure in the door pipe D and all the carriage cylinders will escape. In
shunting the locomotive, the cock on the door pipe D at each end is closed, as also
the nearest vehicle's end door cock before uncoupling.
The cocks are open when the handle stands across the pipe, and shut when the
handle is extended in the same direction as the pipe, that is, along the pipe. When
coupling a carriage whose door pipe is not charged with compressed air or with air
of a lower pressure than prevails in the door pipe of the train to which the carriage
is to be attached, the door pipe throughout the train should be emptied and not
charged again until it is desired to close or fasten all the doors; the necessity for
this is of course plain to any one who understands the operation of compressed air
and the discharge valve E. When a carriage is about to be detached from a train,
the air pressure in the train door pipe D should be gradually reduced by the official
on the locomotive or guard's van before unfastening the doors and before uncoupling
said carriage, so that the air stored in the discharge valve E of the detached
carriage will not be at too high a pressure. No inconvenience would result from
neglecting to do so, however. The driver should of course be careful to have a
high reserve pressure in the reservoir B when extra carriages have to be added.
The same reduction of pressure per square inch to unfasten the doors on long
or short trains is required, but the quantity to be discharged from the three-way
valve C on the locomotive from the door pipe will of course depend on the lengt
of the train.

page_text: As one set of railway managers may consider a modification in some of the
details of this invention in a given direction an improvement, whilst another set
might consider that a modification in a different direction would be an improve-
ment, I do not confine myself to any particular mode of constructing the parts
that I claim as my invention, because, with the description and drawings which I
have given, the most ordinary mechanic could modify or adapt the different
appliances to varying circumstances without departing from the spirit of my inven-
tion. It is, of course, easy to close, fasten and unfasten all the doors of a train
simultaneously and to keep them closed until released by an official; but this of
itself, however simply and effectively it may be obtained, would be a greater
danger to passengers and railway proprietors than the old system of fastening the
doors separately.
The advantages of my present invention in conjunction with my former one, and
the results aimed at and obtained may be briefly summarised as follows:-
I. An authorized official can close and fasten and unfasten all the carriage
doors throughout the train from a given point such as the locomotive by
compressed air.
II. The doors close gently and without slamming and any door may be kept
almost wide open for any length of time without affecting the travel or fastening
of the other doors; and were a person caught by a closing door it would not
hurt him although as soon as a door has once been fully closed by the
appliances it cannot be again opened more than about an inch without the
consent and co-operation of the guard or driver, or other authorized official,
unless circumstances warrant a passenger disconnecting the door from the
apparatus.
III. The guard in the van as well as the official on the locomotive can unfasten
the doors, and the appliances do not open doors, but simply unfastens them.
IV. All the doors of travelling trains can be securely and safely fastened to
prevent platform accidents, and accidents caused through insecure doors flying
open during transit, and the official need not release the doors until the train has
come to a state of rest.
V. In the event of an accident to a train, and any other time that circumstances
justify passengers in doing so, they can disconnect the doors from the apparatus
easily and quickly.
VI. The operation of the appliances is free from noise, and does not interfere
with the present mode of passengers opening and closing the doors while a train is
at the platform.
VII. Any door can be opened separately when required for special ticket
collecting or for any other purpose by station officials.
VIII. In fitting the appliances to the vehicles of trains there is no alteration to
carriage stock necessary, and the appliances may be fitted upon carriages in many
different ways according to circumstances, and there is no necessity for uniformity
throughout the train; for instance, the appliances may be fitted upon the roof of
one carriage and on the foot board of some others, and so on, on the different
vehicles constituting one train.
IX. The appliances can be fitted conveniently upon any existing carriages, and
be worked on mixed trains, and can be made to operate on all the doors whether
some be sliding and others hinged, and whether some of the doors be at the ends
and the other vehicles constituting the same train have side doors.
✗. One operating cylinder for each carriage can control all the doors of said
carriage.
XI. Coupling or uncoupling can be done with ease in less than three seconds of
time.
XII. In the event of an accident to a train, a sudden reduction of the air
pressure in the main pipe unfastens all the doors automatically.
XIII. Only about th of the air contained in the carriage pipe need be
discharged to empty the door cylinders.
B

page_text: XIV. The additional weight to carriages need not on an average exceed 16 lbs.
per door, and the additional weight to the locomotive and guard's van, and the
space occupied, are trifling.
XV. No matter where the locomotive may be attached, the authorized official
has always a complete control over the doors.
XVI. The appliances are fitted to the outside of carriages, and are practically
out of sight and out of the way, and the first cost is trifling and costing very little
to maintain, whilst they are durable and so simple that porters can quickly under-
stand them and will save a large amount of labor at stations.
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 1
claim is-
1st. In means for closing and fastening and unfastening railway carriage doors,
the employment of a three-way valve (such as c) having auxiliary ports such
as cc for replenishing any leakage from the door-operating service, substantially
as set forth.
2nd. In means for closing and fastening and unfastening railway carriage doors,
the employment of a discharge valve (such as E) so constructed and arranged
that the sudden discharge of air from the door pipe will open communication
between the door cylinder and the atmosphere so that the air can pass into
the latter without having first to pass' through a considerable length of pipe,
and so that all the air contained in the door pipe need not be discharged
each time it is desired to unfasten the doors, substantially as and for the purposes
set forth:
3rd. In means for closing and fastening and unfastening railway carriage doors,
the employment of a stop piece (such as M) substantially as and for the purposes
herein described and explained.
4th. In means for closing and fastening and unfastening railway carriage doors,
the combination of a cross lever (such as G) with a pair of door-closing rods (such
as H) substantially as and for the purposes herein described and explained.
5th. The combination with means for closing and fastening and unfastening
railway carriage doors of a sliding bolt (such as L) adapted to disconnect said
doors from said means as set forth.
Dated this Fourth day of November One thousand eight hundred and
ninety-two.
R. N. MONTGOMERY.