IMPROVEMENTS IN BRAKE APPARATUS FOR RAILWAY VEHICLES:
Year: 1878

page_text: LETTERS PATENT to Francis William Webb, of Crewe, in the County of
Chester, Mechanical Engineer, for the Invention of "IMPROVEMENTS IN BRAKE
APPARATUS FOR RAILWAY VEHICLES:"
Sealed the 24th April 1878, and dated the 20th February 1878.
PROVISIONAL SPECIFICATION left by the said Francis William Webb at the
Office of the Commissioners of Patents on the 20th February 1878.
FRANCIS WILLIAM WEBB, of Crewe, in the County of Chester, Mechanical.
Engineer. "IMPROVEMENTS IN BRAKE APPARATUS FOR RAILWAY VEHICLES."
My Invention relates to an arrangement and combination of brake apparatus
which can be applied to the locomotive and carriages of a railway train, and which
apparatus can be brought into operation by the engine driver or the guard, or, if
desired, by the passengers in the train; and it is also automatic when the connec-
tions between the carriages are broken or separated, so that the carriages become
detached; and my Invention consists in a double piston, that is, two pistons, one of
larger area than the other, each fitting into a cylinder, so that when air or other
elastic fluid pressure is brought into the large cylinder, it also passes at the same
time by a pipe or passage through a valve, which closes against its return, into the
small cylinder, and the pressure in the large cylinder thus causes the piston to
travel towards the small cylinder, and this movement is conveyed by levers and
rods to the brake levers, and withdraws the brakes from the wheels, so that the
pressure thus used has to be kept in constant action when the brakes are not to be
applied; and when this pressure is allowed to pass out of the pipes (which can be
done by opening a cock or valve by the driver or guard, or by the passengers 'if
there be a valve or cock in each carriage, or by the separation of the train), the
pressure of the acting fluid leaves the large cylinder, but it is retained by the said
inlet valve in the small cylinder, and the pressure thus retained then acts to force
the double piston towards the large cylinder, and this movement of the piston is
conveyed through the levers and connections to put on the brakes.

page_text: "
For brakes acting by pressure I prefer to employ a double piston formed by a
disc or ordinary piston at one end, with a hollow cylinder attached to form a smaller
ram piston," the cavity in the ram holding sufficient air to give the required move-
ment with but small reduction in the pressure of the air retained; but combined
with the hollow ram piston there may be an air cistern, or a solid or disc piston may
be used in place of the hollow rain piston combined with a reservoir for the air or
other elastic fluid.
The two cylinders may be formed in one casting attached to the vehicle framing,
and this casting is or may be made to carry the fulcrum of the lever, which is made
at one end to engage with the ram part or connection of the double piston, and at
the other end is connected with the brake rods and levers.
The hole in the lever for the fulcrum pin is or may be slotted, or other arrange-
ment may be used (such as allowing the cylinder or fulcrum pin to move slightly),
so that if the brake blocks come against one set before they come against the other
set of wheels, the lever can give way upon its fulcrum until the pressure is also
brought equally upon both sets of brake blocks.
Instead of the double piston being moveable in the cylinders, the double piston
may be fixed, and the cylinders may be connected and arranged to slide upon the
pistons.
The apparatus above described is or may be used when, instead of constant
pressure in the pipes, there is a constant vacuum when the brakes are not to act;
and the apparatus is also brought into action in like manner, except that, instead as in
the first case, pressure being let out to apply the brakes, it is let into the pipes; but
when vacuum is employed as the actuating force the valve between the small cylinder
and the pipe is arranged to open outwards, so that when a vacuum is formed in the
. small cylinder it is retained (except loss by leakage). The cavity or reservoir in
connection with the small cylinder for vacuum actuated apparatus need not be so large
as when brakes are put on by pressure above that of the atmosphere.
When a constant vacuum is employed, as above explained, the double piston is
moved by the vacuum towards the large cylinder, and when the atmosphere is
allowed to enter the pipes, and thus into the large cylinder, it puts on the brakes by
moving the double piston towards the small vacuum cylinder.
In place of double piston and cylinders two bellows, or bags, or diaphragms, or
corrugated metal discs may be employed, one connected to the other, and one of
larger area than the other, so that when both the large and small bellows are
exhausted, the connection between the two bellows will move towards the larger
bellows, and take off the brakes; and when the air is allowed to enter the larger
bellows the motion is reversed, and the brakes are put on. The two bellows or bags
is or may be made out of one bag divided into two compartments, one of greater
area than the other.
Another part of my Invention relates to brakes put on by a friction drum or
drums brought in contact with a drum on the axle of the vehicle, the revolving of
this drum or drums acting upon a rope or chain connected with the brake levers to
put on the brakes, and consists in arranging a friction drum apparatus on each
vehicle, and in combining with it a cylinder having a piston connected with the 4
lever carrying the friction drum or drums, this cylinder being connected with the
pipes conveying the pressure or vacuum, so that the brakes can be put on when
required, or automatically when constant pressure or vacuum is used.
Another part of my Invention relates to a mode of obtaining vacuum for working
continuous vacuum brakes, which consists in arranging so that the action of the
blast pipe of the engine when in motion, and of a jet of steam in the blast pipe when
the engine is at rest, will produce and maintain the vacuum required, a connecting
pipe being arranged between the blast pipe chamber or smoke box and the pipes
passing between the vehicles of the train."
'Another part of my Invention relates to the mode of coupling up the pipes con- 5
veying pressure or vacuum from one vehicle to another, and consists in arranging the
end of the pipe at one side at one end of the vehicle, and at the other side at the opposite

page_text: end of the vehicle, and then coupling between the vehicles by an elastic, flexible, or
other tube passing more or less diagonally from the end of one pipe on one vehicle
to the end of the other pipe on the adjoining vehicle. The elastic or flexible con-
nection may have half of its length attached to each vehicle, and the coupling may
be placed inidway in its length. By this arrangement with one connecting pipe
only the vehicle will be in the right position for connection with adjoining vehicles,
whichever end it is foremost, if the coupling is suitable.
I also obviate the inconvenience of couplings by making the elastic, or flexible,
or other tube with, say, "he" couplings at both ends, and having "she" couplings
on the ends of the pipes on the vehicle, or vice versa, one of these tubes being
always attached with a cap for closing one end to each vehicle. It will with this
arrangement be only necessary at times to remove the flexible or other tube from
one and secure it to the other end of the vehicle.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Francis William Webb in the Great Seal Patent Office on the 19th
August 1878.
FRANCIS WILLIAM WEBB, of Crewe, in the County of Chester, Mechanical
Engineer. “IMPROVEMENTS IN BRAKE APPARATUS FOR RAILWAY VEHICLES."
My Invention relates to an arrangement and combination of brake apparatus
which can be applied to the locomotive and carriages of a railway train, and which
apparatus can be brought into operation by the engine driver or the guard, or, if
desired, by the passengers in the train; and it is also automatic when the connec
tions between the carriages are broken or separated, or the carriages become
detached; and my Invention consists of a double piston, that is, two pistons con-
nected together and enclosed in a double cylinder, one cylinder and piston being of
larger diameter than the other. The ends of the cylinders are connected. by a pipe
or passage through the piston, in which is fitted a valve (by preference a Perreaux's
rubber valve) opening towards the small cylinder, or the valve may be placed.at
or near the end of the small cylinder with separate pipe connection.
When air or
other elastic fluid pressure is admitted into the large cylinder, it also passes through
the valve (which closes against its return) into the small cylinder, and the pressure
in the large cylinder acting on the greater area causes the piston to travel towards
the sinall cylinder, and this movement is conveyed by suitable mechanisni to the
brake levers, and withdraws the brake blocks from the wheels, the pressure being.
maintained to keep the brake out of action; but when this pressure is allowed to
pass out of the pipes (which can be done by opening a cock or valve by the driver
or guard, or by the passengers if there be a valve or cock in each carriage), or by the
separation of the train, the pressure of the acting fluid leaves the large cylinder,
but is retained by the said inlet valve in the small cylinder, and the pressure thus.
retained forces the double piston towards the large cylinder, and acting through the'
levers and connections puts on the brakes,

page_text: «
For brakes acting by pressure I prefer to employ a double piston formed by a
disc or ordinary piston at one end, with a hollow cylinder attached to form a smaller
'ram piston," the cavity in the ram holding a sufficient amount of air to give the
required movement with but a small reduction in the pressure of the air retained;
but combined with the hollow ram piston there may be an air cistern, or a solid or
disc piston may be used in place of the double ram piston, combined with a reservoir
for the air or other elastic fluid.
The two cylinders may be formed in one casting attached to the vehicle framing,
and this casting is or may be made to carry the fulcrum of the lever, which is made
at one end to engage with the ram part or connection of the double piston, and at
the other end with the brake rods and levers.
The hole in the lever for the fulcrum pin is or may be slotted, or other arrange-
ment may be used (such as allowing the cylinder or fulcrum pin to move slightly);
so that if the brake blocks come against one set of wheels before they come against
the other set, the lever can give way upon its fulcrum until the pressure is brought
equally upon both sets of brake blocks."
Instead of the double piston being moveable in the cylinders, the double piston
may be fixed, and the cylinder or cylinders may be connected and arranged to slide
upon the pistons.
The apparatus above described for a constant pressure may also be used for a con-
stant vacuum by arranging the valve to the small cylinder to open outwards
instead of inwards, and with a suitable arrangement of levers. The constant vacuum
in the pipes will keep the brakes off the wheels by drawing the piston towards the
large cylinder.
When the atmospheric pressure is allowed to enter the pipes, the piston will be
forced towards the small cylinder containing the vacuum, and the brakes will be
applied.
In place of a double piston and cylinder two bellows, or bags, or diaphragms, or
corrugated metal discs may be employed, one connected to the other, and one of
larger area than than the other, so that when both the large and small bellows are
exhausted, the connection between the two bellows will move towards the larger
bellows, and take off the brakes; and when the air is allowed to enter the larger
bellows the motion is reversed, and the brakes are put on. The two bellows or bags
are or may be made out of one bag divided into two compartments, one of greater
area than the other.
Another part of my Invention relates to brakes applied by friction drum or
drums to be brought in contact with a drum on the axle of the vehicle, the revolving
of the drum or drums winding in a rope or chain connected with the brake levers
to put on the brakes, and consists in arranging a friction drum apparatus on cach
vehicle, and in combining with it a cylinder having a piston connected with the
lever carrying the friction drum or drums; this cylinder is connected with the
pipes conveying the pressure or vacuum, so that the brakes can be put on when
required, or automatically when constant pressure or vacuum is used.
Another part of my Invention relates to a mode of obtaining vacuum for working
continuous vacuum brakes, which consists in arranging that the action of the blast
pipe of the engine when in motion, and of a jet of steam in the blast pipe when
the engine is at rest, will produce and maintain the vacuum required, a connecting
pipe being arranged between the blast pipe chamber or smoke box and the pipes
passing between the vehicles of the train."
Another part of my Invention relates to the mode of coupling up the pipes con-
veying pressure or vacuum from one vehicle to another, and consists in arranging
the end of the pipes at one side at one end of the vehicle, and at the other side at
the opposite end of the vehicle, and then coupling between the vehicle by an elastic,
flexible, or other tube passing more or less diagonally from the end of the pipe on
one vehicle to the end of the other pipe on the adjoining vehicle. By this arrange-
ment with one connecting pipe only the vehicle will be in the right position for

page_text: connection with adjoining vehicles, whichever end is foremest, if the coupling is
suitable.
I also obviate the inconvenience of coupling by making the elastic, or flexible,
or other tube with, say, "he" couplings at both ends, having "she" couplings on
the ends of the pipes on the vehicles, or vice versa, one of these tubes with a cap for
closing one end being always attached to each vehicle. It will with this arrange-
ment be only necessary at times to remove the flexible or other tube from one end
and secure it to the other end of the vehicle.
Fig. 1 is a section, Fig. 2 is a side elevation, Fig. 3 a plan, Fig. 4 an end view,
and Fig. 5 is a cross section on the line 1-2, Fig. 1, these Figures illustrating one
modification of the double pistons and cylinders for carrying out my Invention.
The two cylinders a and a¹ are in this modification made with closed outer ends
and with a flange at their inner ends, by which they are bolted together, and 'the
cylinders are secured to the framing of the vehicle, as shown.
bis the double hollow rain piston; at its larger end it has a disc screwed in,
which secures the packing; it has also a hole in its centre in which a Perreaux's
rubber or other valve (c) is placed and secured..
The middle part of the ram (b) is made with a slot, as shown best in Figs. 1 and 5.
Holes form a communication between the ends of the ram.
The smaller end of the hollow ram is also fitted with packing, and is open to the
small cylinder a¹.
When air is admitted into the large cylinder (a), it passes into the small cylinder
(a) through the valve (c) and passages 61 in the middle of the ram.
The slot in the ram is for the lever arm d, which has side projections that enter
cross slots in the ram (b), by which the ram and arm are connected, this arm being.
on a short cross shaft (d) in bearings between the two cylinders, as shown.
To the ends of the shaft (d') are secured arms (2) to which are connected the rods
or gear ds that convey motion to the brakes.
Fig. 6 is a sectional elevation, and Fig. 7 is a plan illustrating the mode of
applying the apparatus shown by Figs. 1, 2, 3, 4, and 5 to the framing of a carriago
or other railway vehicle.
The double cylinders a and a¹ are secured to the middle of the framing, and the
rods d³ from the arms d² on the shaft d' pass to each set of brakes, as shown.
The pipe e for conveying the fluid pressure passes. lengthway of the vehicle.
There is a branch pipe e¹ between the main pipe c and the end of the large
cylinder (a) in which there is a cock, so that, the communication may be cut off
from the main pipe e when desired.
Fig. 8 is a side elevation, and Fig. 9 an end view illustrating another modification
of my Invention, where the pistons are secured to the framing of the vehicle, and.
the cylinders slide thereon.
The pistons are arranged within the cylinders, and packed in a manner similar to
the modification illustrated by Figs. 1 to 5; but the ram part b has a branch from
it with flanges, by which it is secured to the framing of the vehicle, as shown.
The cylinders a and al are bolted together, but there is a gap formed to allow
them to move without coming in contact with the projection from the ram (b).
The fluid pressure is conveyed from the main pipe e by a branch pipe e (connected
with the projection from the ram), and then by a passage into the large cylinder (a),
and through the valve in the piston to the smaller cylinder a¹. There is a shaft or
studs d fixed in the solid part of the projection from the ram to carry the levers or
lever arms d², which are connected at their lower ends by a rod dx that works in a
slot formed between the cylinders, and gives movement to the levers (d) to which.
the rods (3) are connected that convey the motion to the brakes.
Fig. 10 is a side elevation, and Fig. 11 an end view illustrating another modifi-
cation of my. Invention, where bellows are used and arranged to be actuated by a.
partial vacuum.
f is a casting screwed to the framing of the vehicle, to one end of which the large
bellows a are secured, and to the other end the small bellows a' between the two

page_text: inner ends of the large and small bellows a cylindrical casting a² is placed, so as to
slide on guides in the casting f. The inner ends of the bellows are secured to this
casting (a), and at the end nearest the large bellows (a) à valve is fitted opening
from the casting towards the large bellows. The interior of the cylindrical casting
and the smaller bellows are in communication. On the outside of the cylindrical
casting a there are side projections which engage the ends of the levers d²; these
levers are centred on a shaft d' carried in the frame f, and are connected with the
rods d³ to the brake blocks.
A branch pipe e¹ from the main pipe e is connected with the casting f, and com-
municates with the large bellows a.
The bellows in the position shown are under a partial vacuum formed in the
large and small bellows, and the brakes are held from the wheels; but when the
atmosphere is allowed to enter the pipes the large bellows are forced against
the small bellows, and the brakes are applied, as the valve prevents the vacuum,
being destroyed in the smaller bellows.
The modification shown by Figs. 1 to 5 and Figs. 8 and 9 are made to operate by
a partial vacuum for reversing the valve c to the position shown in Fig. 10.
.
Fig. 12 is a sectional elevation, and Fig. 13 a plan illustrating a modification of
my Invention for bringing into and out of action a well-known arrangement of
brake mechanism, in which the brakes are actuated through the winding in of a
rope or chain by a drum or drums on a lever being brought against a drum or drums,
or one or more of the axles.
d2 is a lever to which the rods d³ are connected, which convey motion to the
brakes; this lever carries a pulley d*, around which a rope or chain passes, one end
of which is secured to an arm of the drum lever g, the other end passing over a
pulley carried on the stud or the fulcrum g' of the lever (g), and is then attached
to the spindle of the drum g³.
Above the end of the lever g, and attached to the framing of the vehicle, there is
a cylinder h, the upper end of which is closed and the lower end open; to the under
side of the piston is attached a slotted link h¹, coupled to the lever g. There is also
another lever h² carried by a link from a bracket on the cylinder h, one end of
which is connected with the slotted link h', and the other end has a link h³ jointed
to it, through the slot of which a pin passes in the arm of the lever g. There is a
branch pipe el connecting the upper part of the cylinder h with the main pipe e,
passing from end to end of the carriage.
When a partial vacuum is formed in the main pipe e the piston or ram in the
cylinder his at its highest position, and the lever is held up by the link ¹; but
when the partial vacuum is destroyed by admission of air into the pipe e, the lever g
is allowed to fall and bring the drums g2 in contact with the drums on the axle of
the carriage.
When pressure is used instead of vacuum the piston or ram is forced to the lower
end of the cylinder h, and the upper end of the slot on the link h¹ acts upon the
lever ², so that the link (h³) supports the lever g, and keeps the drums out of
contact; and when the pressure is allowed to pass from the main pipe (e), the lever g,
being no longer supported, drops, and the drums are brought into contact.
The lever g, by another modification, may be held up by a weight or spring, and
then by jointing the links h' and h³ with the lever g, and arranging the slots in
these links above the arm of the lever g; then, with the piston at mid stroke, when
the lever g is held up, pressure in the main pipe e to put on the brakes, acting
through the link h¹ would force the lever g down against the action of the spring or
weight, and vacuum or partial vacuum would draw up the piston and force the
lever g down through the lever h² and link h³.
Figs. 14 and 15 are cross sectional elevations, the one taken at a right angle to
the other, illustrating a method of obtaining a constant partial vacuum.
a is part of the blast pipe of a locomotive, and b and c are nozzles arranged in it;
ex is the junction of a pipe to be connected with the main pipes e passing length-
way of the vehicles, ..

page_text: c¹ is the junction of a pipe through which steam can be admitted direct from the
boiler between the nozzles b and c when desired.
It will be seen that the exhaust from the cylinders will act upon the nozzle b to
produce a partial vacuum in the pipe ex, and that when the exhaust is not escaping
a partial vacuum may be formed in the pipe ex by the steam admitted to the nozzles
direct from the boiler.
In any convenient part of the pipe e, that is, on the engine, there is a valve which.
allows the air to be withdrawn, but closes against its return, so that when the
vacuum or partial vacuum is formed it will be retained as long as desired, except
loss by leakage.
I have now particularly described the nature of my Invention, and the modes of
carrying the same into effect, and claim as my Invention,-
Firstly. The system or mode of actuating brakes by differential pistons and
cylinders, or differential bellows, or like apparatus, where the pressure or partial
vacuum acts in one direction simultaneously on both pistons or bellows, and when
this pressure or vacuum ceases to act, the pistons or bellows re-act in consequence of
the pressure or vacuum reserved in one of the cylinders or bellows, substantially as
herein-before described, and illustrated by the Drawings.
Secondly. The combination and arrangement of mechanism for actuating brakes,
as herein-before described, and illustrated by Figs. 1 to 10 inclusive of the
Drawings.
Thirdly. The combination and arrangement of mechanism for actuating brakes, as
herein-before described, and illustrated by Figs. 12 and 13 of the Drawings.
Fourthly. The arrangement of the main pipes (e) and connections in railway
vehicles, substantially as herein-before described, and illustrated by the Drawings.
Fifthly. The mode of obtaining a continuous partial vacuum by means of the
exhaust steam from a locomotive for actuating brakes, substantially as herein-before
described, and illustrated by Figs. 14 and 15 of the Drawings.
In witness whereof, I, the said Francis William Webb, have hereunto set my
hand and seal, this Fourteenth day of August, in the year of our Lord One
thousand eight hundred and seventy-eight.
F. W. WEBB. (L.S.)