Improvements in or connected with Automatic Vacuum Brake Apparatus for Railway Vehicles, chiefly applicable to Trains from which Carriages are to be Slipped.
Year: 1891

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Date of 'Application, 21st Sept., 1891
Complete Specification Left, 21st June, 1892-Accepted, 3rd Sept., 1892
PROVISIONAL
SPECIFICATION.
Improvements in or connected with Automatic Vacuum Brake
Apparatus for Railway Vehicles, chiefly applicable to Trains
from which Carriages are to be Slipped.
I, FREDERICK WILLIAM LARKHAM 21 Kerrison Road Battersea S.W. Guard
London & South Western Railway do hereby declare the nature of this invention
to be as follows:-
My invention has reference to improvements in connection with the use of the
automatic vacuum brake for railway vehicles, and consists in an improved form of
coupling by which when it is desired to slip coaches the vacuum may be preserved
and therefore the brake power of the vacuum may be preserved in the portion of
the train which is slipped.
At the present time it will be understood that certain disadvantages are inherent
in the application of the vacuum brake from this reason, that where slip coaches
are added to a train and are detached at a certain station, that these vehicles which
form the slipped or hind portion of the train are not provided with the automatic
vacuum brake but are controlled by a hand brake. The pipes are not charged in
consequence of the difficulty found, that if the whole of the train was charged with
vacuum and the hind portion of it was then slipped, as is known, the action of
detaching the hind portion of the train in this condition would cause the brake to
act and stop both portions of the train. It will therefore be readily seen that it is
practically impossible to apply the vacuum brake throughout the whole of a train 'a
portion of which has to be slipped. On the other' hand it is eminently desirable
that where the vacuum brake is adopted it should be available throughout the
whole of the train including the slip portion, otherwise the train is not provided
with sufficient brake power under control of the driver.
The object of my invention is to provide such a coupling and means by which
the vacuum brake can be applied throughout the whole of the train including the
portion to be slipped and allowing the vacuum brake to be used in the slip portion
after detachment if so desired, the disadvantages previously described with
reference to applying it to the first portion being obviated.
'I
carry it out in the following manner:
Attached to the last carriage of the front portion of the train, that is, the
carriage immediately in front of the first slip carriage, I provide a coupling which
I term, the intermediate coupling, the left hand portion of which is coupled in
the ordinary way to the flexible pipe coupling on the end carriage of the front
portion of the train. This intermediate coupling consists of a casting, the left
hand end as previously described fitted to the carriage referred to.
The right
hand end is provided on the interior with a clapper valve hinged on the upper
side of the interior. A seating is provided also on the upper portion of the
interior so that the valve may lie in that position when the vacuum brake is on
throughout the whole of the train. A spring is provided on the back of the
clapper valve so that should the vacuum brake be applied after the separation
or too suddenly and the clapper valve be blown away from the aperture, the
action of the spring coming against the top portion of the intermediate casting
tends to force it down again closing the aperture, and. so allows the driver to
create the vacuum again in the ordinary way.
I provide an independent piece in the form of a coupling connected to the
front carriage of that portion of the train to be slipped, this special piece being
provided in a like manner with a clapper valve hinged to the upper portion of

page_text: the interior of the coupling similar to that described with reference to the right
hand portion of the intermediate piece. A similar seating is provided on the
upper side of the interior of the coupling. The faces of the valves are provided
by preference with indiarubber.
The action of my invention is as follows:-
As is well known, in the carriage (which is usually a guard's van) comprising
the first carriage of the portion of the train to be slipped, apparatus or means are
provided for detaching the ordinary iron couplings so that the hind portion or slip
portion of the train may be separated from the other portion of the train for the
purposes of slipping. I do not in my invention propose to alter these arrangements.
The guard or other individual who operates the slipping apparatus, does so in the
usual way.
As soon as the portions of the train have separated to the extent that the tube
coupling becomes horizontal, the valves, the one in the right hand end of the inter-
mediate piece and the other in the coupling attached to the slip carriage, fall
closing the apertures, the couplings come asunder and the valves being in the
position closing the apertures are held in that position by atmospheric pressure.
By this means air is excluded from the pipes.
In order that, before the coupling takes place, to ensure that the valves are
normally free of the apertures as previously referred to, I provide a hole at the
side of the casting, by which through the means of a pin inserted before the
coupling the valves may be held in position. This refers to both of the parts
which form the coupling on the intermediate piece and on the piece attached to the
slip carriage. After the coupling takes place and the pin is withdrawn, set screws
are inserted in the holes referred to. Immediately the valves are in the free
position leaving the apertures open, pins are provided on the interior rim of the
oupling, one on each of the couplings, so that when the coupling takes place the
pius are inserted for guidance through a hole and hold or lock the clapper valve in
its open position for the vacuum to operate.
My further improvements consist of making some provision for overcoming the
difficulty in accidents that now arise in consequence of moisture or water freezing
in the pipes, so rendering the brake non-effective.
For this purpose I provide in the ordinary coupling, on its underneath side, that
the casting is bulged out forming a small recess on the pipe side of the rims where
the couplings join. In this recess any moisture or water that may be in the pipes
is retained and if frozen will not interfere with the free passage throughout the
pipes of the train. This would be provided in every coupling.
In order that my invention may be automatic not only in reference to slipping
coaches and thereby retaining the vacuum in each portion of the train, but also in
the event of a break away or severance of the train accidentally, at my special
coupling where the said carriage is joined on to the train.
Attached to the lever in the slipping coach I fix a rod projecting through the
end of the coach and supported by suitable brackets fixed on to the coach, or rest
upon the bevel of the casting which normally would be projecting through two
links which links are connected by chain to two stops or plugs, one fitted at each
side of the valves, the oue valve in the intermediate piece and the other in the
coupling at the end of the main portion of the train, which goes forward.
. I
The action of this portion of my invention is as follows:-
Should an accidental severance take place at this coupling, the rod connected to
the slipping lever being through the links and holding them firmly, as the vehicles
separated and the tendency of the pipe is to assume a horizontal position the
plug is pulled out of the intermediate piece and also out of the end of the
coupling attached to the main portion of the train, thereby admitting air,
destroying the vacuum and putting on the brakes.
When an ordinary slip takes place by authority, the lever is operated and the
rod connected to the said lever is moved clear of the links so that as the pipes
rise the links and plugs rise with them and when the separation takes place the

page_text: valves act as hereinbefore described, no air being admitted as the plugs retain
their position.
Another method of carrying out my invention in lieu of that hereinbefore
described, is as follows:-
I arrange inside the coupling that the inner seating terminates in a diagonal
form, and hinged on the upper side of the inside of the coupling is a clapper valve.
A projection on the said valve is arranged beyond the hinge or fulcrum and means
are provided to allow it to be operated. In the coupling which is connected to the
end carriage of the front portion of the train I arrange that a pin is provided
projecting beyond the face of the coupling. This pin is of such a length that in
the act of coupling the pin operates on the end of the clapper valve beyond its
fulcrum and moves it into a horizontal position, freeing the aperture in the tube,
and it starts its operation when the couplings have approached each other or been
connected at a pre-arranged distance, to the extent that the clapper valve is in its
working or horizontal position when the couplings are together and air tight.
When the disconnection or slip takes place the pin is withdrawn to a very slight
extent before the actual separation of the couplings takes place, the clapper valve
falls and is held in that position by suction. The vacuum is not perceptibly
destroyed to any extent.
Dated this 2nd day of January 1892.
JOHN P. O'DONNELL,
2, Great George Street, Westminster, London, S. W.,
Agent for the said Applicant.
COMPLETE SPECIFICATION.
Improvements in or connected with Automatic Vacuum Brake
Apparatus for Railway Vehicles, chiefly applicable to Trains
from which Carriages are to be Slipped.
I, FREDERICK WILLIAM LARKHAM, of 21 Kerrison Road, Battersea, London,
in the County of Surrey, Guard, London & South Western Railway, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following.
statement:-
My invention has reference to improvements in connection with the use of the
automatic vacuum brake for railway vehicles, and consists in an improved form of
coupling by, which when it is desired to slip coaches the vacuum may be preserved
and therefore the brake power of the vacuum retained in the portion of the train
which is slipped.
At the present time it will be understood that certain disadvantages are inherent
in the application of the vacuum brake from this reason, that where slip coaches
are added to a train and are detached at a certain station, that those vehicles which
form the slipped or hind portion of the train are not provided with the automatic
vacuum brake but are controlled by a hand brake. The pipes are not charged in
consequence of the difficulty found, that if the whole of the train was charged with
vacuum and the hind portion of it was then slipped, as is known, the action of
detaching the hind portion of the train in this condition would cause the brake to
act and stop both portions of the train. It will therefore be readily seen that it is
practically impossible to apply the vacuum brake throughout the whole of a train a
portion of which has to be slipped. On the other hand it is eminently desirable
that where any brake is adopted it should be available throughout the whole of the
train including the slip portion, otherwise the train is not provided with sufficient
brake power under control of the driver.
The object of my invention is to provide such a coupling and means by which the
vacuum brake can be applied throughout the whole of the train including the
portion to be slipped, and allowing the vacuum brake to be used in the slip portion

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after detachment if so desired, the disadvantages previously described with
reference to applying it to the first portion being obviated.
I carry out my invention in the following manner :-
Attached to the last carriage of the front portion of the train, that is, the
carriage immediately in front of the first slip carriage, I provide a coupling which
I term the intermediate coupling, the left hand portion of which is coupled in the
ordinary way to the flexible pipe coupling on the end carriage of the front portion
of the train. This intermediate coupling consists of a casting, the left hand end as
previously described, fitted to the carriage referred to. The right hand end is
provided on the interior with a clapper valve hinged on the upper side of the
interior. A seating is provided also on the upper portion of the interior so that the
.valve may lie in that position when the vacuum brake is on throughout the whole
of the train..
I provide an independent piece (or two pieces as hereinafter shewn) in the form
of a coupling connected to the front carriage of that portion of the train to be
slipped, this special piece being provided in a like manner with a clapper valve
hinged to the upper portion of the interior of the coupling similar to that described
with reference to the right hand portion of the intermediate piece. A similar
seating is provided on the upper side of the interior of the coupling. The faces of
the valves are provided by preference with indiarubber.
The action of my invention is as follows:-
As is well known, in the carriage (which is usually a guard's van) comprising the
first carriage of the portion of the train to be slipped, apparatus or means are
provided for detaching the ordinary iron couplings so that the hind portion or slip
portion of the train may be separated from the other portion of the train for the
purposes of slipping. I do not in my invention propose to alter these arrangements.
The guard or other individual who operates the slipping apparatus, does so in the
usual way.
As soon as the portions of the train have separated to the extent that the tube
coupling becomes horizontal, the valves, the one in the right hand end of the
intermediate piece and the other in the coupling attached to the slip carriage, fall
closing the apertures, the couplings come asunder and the valves being in the
position closing the apertures are held in that position by atmospheric pressure.
By this means air is excluded from the pipes.
In order that, before the coupling takes place, to ensure that the valves are
normally free of the apertures as previously referred to, I provide a hole at the
side of the casting, by which through the means of a pin inserted before
the coupling the valves may be held in position. This refers to both of the
parts which form the coupling, on the intermediate piece and on the piece attached
to the slip carriage. After the coupling takes place and the pin is withdrawn, set
screws are inserted in the holes referred to.
Immediately the valves are in the free position leaving the apertures open, pins
are provided on the interior rim of the coupling, one on each of the couplings, so
that when the coupling takes place the pins are inserted for guidance through a
hole and hold or lock the clapper valve in its open position for the vacuum
to operate.
My further improvements consist of making some provision for overcoming the
difficulty in accidents that now arise in consequence of moisture or water freezing in
the pipes, so rendering the break non-effective.
For this purpose I provide in the ordinary coupling, on its underneath side, that
the casting is bulged out forming a small recess on the pipe side of the rims where
the couplings join. In this recess any moisture or water that may be in the pipes
is retained and if frozen will not interfere with the free passage throughout the
pipes of the train. This would be provided in every coupling.
In order that my invention may be automatic not only in reference to slipping
coaches and thereby retaining the vacuum in each portion of the train, but also in
the event of a break away or severance of the train accidentally at my special

page_text: coupling where the said carriage is joined on to the train, attached to the lever in
the slipping coach I fix a rod projecting through the end of the coach and supported
by suitable brackets fixed on to the coach, or resting upon the bevel of the casting
which normally would be projecting through two links, which links are connected
by chain to two stops or plugs, one fixed at each side of the valves, the one valve
in the intermediate piece and the other in the coupling at the end of the main
portion of the train, which goes forward.
The action of this portion of my invention is as follows :—
Should an accidental severance take place at this coupling, the rod connected to
the slipping lever being through the links and holding them firmly, as the vehicles
separated and the tendency of the pipes is to assume a horizontal position, the plug
is pulled out of the intermediate piece and also out of the end of the coupling
attached to the main portion of the train, thereby admitting air, destroying the
vacuum and putting on the brakes.
When an ordinary slip takes place by authority, the lever is operated and the
rod connected to the said lever is moved clear of the links so that as the pipes rise
the links and plugs rise with them and when the separation takes place the
valves act as hereinbefore described, no air being admitted as the plugs retain their
position.
Another method of carrying out my invention in lieu of that hereinbefore
described, as follows:-
I arrange inside the coupling that the inner seating terminates in a diagonal
form, and hinged on the upper side of the inside of the coupling is a clapper valve.
A projection on the said valve is arranged beyond the hinge or fulcrum and means
are provided to allow it to be operated. In the coupling which is connected to the
end, carriage of the front portion of the train I arrange that a pin is provided
projecting beyond the face of the coupling. This pin is of such a length that in
the act of coupling the pin operates on the end of the clapper valve beyond its
fulcrum and moves it into a horizontal position, freeing the aperture in the tube,
and it starts its operation when the couplings have approached each other or been
connected at a pre-arranged distance, to the extent that the clapper valve is in its
working or horizontal position when the couplings are together and air tight.
When the disconnection or slip takes place the pin is withdrawn to a very slight
extent before the actual separation of the couplings takes place, the clapper valve
falls and is held in that position by suction. The vacuum is not perceptibly
destroyed to any extent.
An obvious modification and one which is illustrated and will be referred to
hereafter consists in extending the pin connected to the end of the clapper valve
and making it of such a length as to obviate the necessity of providing any pin in
the opposite coupling for the purpose of directly operating on the extended end of
the clapper valve. The action is the same. only the pin is then needed.to
normally project very slightly beyond the facing of the coupling when the
couplings are uncoupled. It will also be observed from the drawings that two
intermediate pieces are provided, which are practically identical in form, the object
being that the ends of the ordinary couplings may be left as usual and not provided
with anything special in the nature of valves. This obviates the necessity of having
the hind carriage of the first portion of the train provided with a special coupling
having a clapper valve inserted.
In order that my invention may be better understood and more readily carried
into effect I will proceed to describe the drawings hereunto annexed.
Figure 1 is a sectional view of the hose, the ordinary coupling, the intermediate
piece, and the end coupling of the hind carriage of the first portion of the train,
such coupling being provided as shown with a valve.
Figure 2 is a left hand end view of the intermediate piece, and Figure 3: is a
right hand or front view of the intermediate piece.
Figure 4 is a sectional view of my apparatus, showing the hose. This illustrates.

page_text: '
.
1
.
2
an intermediate piece.
The difference between this figure and Figure 1 ·being in
the actuation of the valves.
It must be understood that if desirable the intermediate piece in Figure 4 itself
can be abolished as if the couplings, that is to say, the coupling on the front of the
slipping coach and the coupling on the hind portion of the last carriage in the front
portion of the train, are provided with valves operated similarly to that described
in Figure 4, then an intermediate piece would not be necessary, as when the
slipping takes place both valves come down on to their seatings and retain the
vacuum in each portion of the train.
Figure 5 is a side view of the coupling of the last carriage of the foremost part
of the train.
Figure 6 is a section of the hose and the two intermediate couplings. This is
practically what is illustrated in Figure 1, arranged so that both the ends of the
ordinary couplings do not require to be provided with anything special in the
nature of a valve, that is to say that the coupling on the slip carriage and
the coupling on the last vehicle of the first portion of the train may be ordinary
couplings, the two intermediate pieces acting as one, being inserted between them.
When it is not required to use the last carriage as a slip carriage, the two inter-
mediate pieces are taken away and the two ordinary couplings coupled together the
same as the ordinary carriages. It will thus be seen that no carriages need be
permanently provided with special couplings.
Figure 7 shows a part sectional view of the front portion of the slip coupling,
with the lever for operating the ordinary mechanical couplings, connected to which
lever is the rod passing through the loops on the intermediate couplings.
The same letters refer to the same parts in the several figures of the drawings.
a is the hose pipe, 6 are the ordinary couplings I provide without anything
special, c is the intermediate coupling of Figure 1; d is the clapper valve in the
intermediate coupling, e is the clapper valve in the ordinary coupling; d¹ is
the raised piece on the end of the valve into which the pin on the fixed coupling
locks and holds the valve in the raised position when the coupling has taken
place. e is a similar raised piece and for the same purpose. f is the spring
attached to the coupling a; g is the spring attached to the coupling e; h, ¹ are
holes provided in the couplings for the insertion of the pin to hold the valve in the
raised position in the act of coupling. is the fulcrum upon which the valve
works, d³ is the extension of the valve d, e is the extension of the valve d' is the
pin connected to the extension of the valve d, e is the pin connected to the
extension of the valve e; j are the recesses in the end part of the couplings for
the purpose of collecting any moisture; c¹ is the second half of the intermediate
coupling Figure 6; k is the lever for operating the mechanical couplings (the
ordinary iron couplings) and also operates the rod 1 which moves free of the rings m
when the lever is moved to its full position.
€,
With reference to the action of my apparatus Figure 4, in the act of coupling
the ends of the pins d' and e¹ are pressed backward inside the couplings by the
facings of the couplings and by that means the valves are raised through their
extensions d³, e³, when the coupling is complete. The indiarubber rings surrounding
the couplings are together before the valve is completely raised in order to exclude
as far as possible the air.
Although I have described and illustrated the operation of my apparatus as in
Figure 4 through an extension in connection with the pin d, yet an obvious
modification would be that a similar extension be provided on the other side of the
fulcrum d² so that would practically be a cross bar with a straight connection to
the valve working further back in the coupling and always working horizontally
instead of vertically, but this modification is not one which I should prefer.
ง In Figure 7 m are the rings on the ends of the plugs which, should an accidental
break away take place, are withdrawn through the rod l not being operated; the
couplings assuming a horizontal position as the vehicles separate, the plugs are held

page_text: by the rod and are withdrawn from the couplings, admitting air, destroying the
vacuum, and applying the brakes.
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 hose couplings for automatic brake apparatus for railway vehicles, the
provision of a valve such as d, operating that when coaches are slipped the
vacuum is retained in the slipped portion of the train, substantially for the purposes
herein described and as illustrated in the accompanying drawings.
2. In hose couplings for automatic brake apparatus for railway vehicles, the
provision of a valve such as d and extension of the valve such as d, and a pin
operating in connection therewith, such as d', operating that when coaches are
slipped the vacuum is retained in the slipped portion of the train.
3. In hose couplings for automatic brake apparatus for railway vehicles,
arrangements whereby in any accidental severance of the couplings air is admitted
to the pipes thereby putting the brakes on, substantially as described and as
illustrated in the accompanying drawings.
Dated this 21st day of June 1809
JOHN P. O'DONNELL,
2, Great George Street, Westminster, London, S.W.,
Agent for the said Applicant.
JOHN P. O'DONNELL,
2, Great George Street, Westminster, London, S. W.,
Agent for the said Applicant.