IMPROVEMENTS IN RAILWAY BRAKES AND IN PARTS CONNECTED THEREWITH
Year: 1876

page_text: LETTERS PATENT to Alexander Glavin, of Lee, in the County of Kent, for the
Invention of "IMPROVEMENTS IN RAILWAY BRAKES AND IN PARTS CONNECTED
THEREWITH." Partly a communication from abroad by Duncan Gavin, of Lec,
in the County of Kent, but at present of Gothenburg, Sweden.
Sealed the 21st October 1876, and dated the 4th May 1876.
PROVISIONAL SPECIFICATION left by the said Alexander Gavin at the Office
of the Commissioners of Patents on the 4th May 1876.
"IMPROVEMENTS IN
ALEXANDER GAVIN, of Lee, in the County of Kent.
RAILWAY BRAKES AND IN PARTS CONNECTED THEREWITH." Partly a communication
from abroad by Duncan Gavin, of Lee, in the County of Kent, but at present of
Gothenburg, Sweden.
According to this Invention a column of fluid, which may be water, with a
suitable proportion of glycerine to prevent freezing and oxydation, is applied along
the train in pipes which are connected between the carriages by flexible or sliding
joints or parts. When the carriages close up against one another, that is, when the
speed is checked, the column is compressed, and the compressed fluid is caused to
act through branch pipes on suitable piston mechanism for putting the brakes on,
thus stopping the train.
According to a modified arrangement cach carriage is fitted with a cylinder
containing a column of fluid, and having a piston at cach end with its rod running
to the end of the carriage, where it abuts against or is connected to the piston rod
from the adjoining carriage; the closing-up of the carriages forces the piston rods
against one another, and thus compresses the fluid between the pistons in the
cylinder, which, by suitable piston mechanism connected thereto by branch pipes,
is made to put on the brakes; or the rods may, by chains and pulleys, be arranged
so as to be in tension instead of in compression when actuated. The buffers may
be connected to a cross bar or double lover jointed in the middle of the piston rod,
and thus further the same object; at the same time, when going round a curve, the
buffers on one side will be as much compressed, as the buffers on the other side will
run out, and thus there will be no action on the fluid columns in the cylinders from
this cause. Or the buffers may work in cylinders filled with fluid in connection
with one another, and with the central or brake cylinder proper.

page_text: To regulate the pressure on the brakes, and to prevent their action when the
train is being set back, a rope, wire, or pipe is led along the train, and by hydraulic,
pneumatic, or steam, or other pressure, a valve or valves on the cylinder or cylinders
of each carriage is opened, closed, or otherwise actuated, or bolts may be arranged
for throwing the brakes out of gear when the train is backed. Springs may be
used instead of or in addition to such appliances, or the buffers and their connections
may be omitted.
The aforesaid pipe or rod connections may be utilized for train-signalling
purposes at all times, except when backing. When the pipes contain steam the heat
of the latter may be utilized for heating purposes.
By omitting the usual couplings and making the said connections serve as
couplings accidents would be prevented, because the connections would break before
any serious accident could occur, part of the train becoming detached.
The water may be supplied from the tender, and must be shut-off' therefrom
when it is to be applied for action; on opening the communication again the water
can return to the tender and the train can be backed.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Gavin in tho Great Seal Patent Office on the 4th November
1870.
ALEXANDER GAVIN, of Lee, in the County of Kent. "IMPROVEMENTS IN
RAILWAY BRAKES AND IN PARTS CONNECTED THEREWITH." Partly a communication
from abroad by Duncan Gavin, of Lee, in the County of Kent, but at present of
Gothenburg, Sweden.
According to this Invention a column of fluid, which may be water, with a
suitable proportion of glycerin to prevent freezing and oxydation, is applied along
the train in pipes which are connected between the carriages by flexible or sliding
joints or parts. When the carriages close up against one another, that is, when the
speed is checked the column is compressed, and the compressed fluid is caused to
act through branch pipes on suitable piston mechanism for putting the brakes on,
thus stopping the train.
According to another or modified arrangement cach carriage is fitted with a
cylinder containing a column of fluid, and laving a piston at each end with its rod
running to the end of the carriage, where it abuts against or is connected to the
piston rod from the adjoining carriage, the closing-up of the carriages forces the
piston rods against one another, and thus compresses the fluid between the pistons
in the cylinder, which, by suitable piston mechanism connected thereto by branch
pipes, is made to put on the brakes; or the rods may, by chains and pulleys, be
arranged so as to be in tension instead of in compression when actuated. The
buffers may be connected to a cross bar or double lever jointed in the middle of the
piston rod, and thus further the same object at the same time; when going round a
curve the buffers on one side will be as much compressed, as the buffers on the other
side will run out, and thus there will be no action on the fluid columns in the
cylinders from this cause. Or the buffers may work in cylinders filled with fluid in
connection with one another, and with the central or brake cylinder proper.
To regulate the pressure on the brakes, and to prevent their action when the
train is being set back, a rope, wire, or pipe is led along the train, and by hydraulic,
pneumatic, or steam, or other pressure, a valve or valves on the cylinder or cylinders
of each carriage is opened, closed, or otherwise actuated, or bolts may be arranged
for throwing the brakes out of gear when the train is backed. Springs may be
used instead of or in addition to such appliances, or the buffers and their connections
may be omitted.
The aforesaid pipe or rod connections may be utilized for train-signalling

page_text: purposes at all times, except when backing. When the pipes contain steam the
heat of the latter may be utilized for heating purposes.
By omitting the usual couplings and making the said connections serve as
couplings accidents would be prevented, because the connections would break before
any serious accident could occur, part of the train becoming detached.
The water may be supplied from the tender, and must be shut off therefrom
when it is to be applied for action. On opening the communication again the water
can return to the tender, and the train can be backed.
According to this Invention then the force derived from the closing up or opening
out of the carriages of a train or of the train as a whole on or from the engine is
when the hand brake is being applied on the engine in front or on the brake van
in rear automatically applied to the brakes of each carriage through the intervention
of a fluid column or columns in pipes or cylinders. Such force, supplimented or
not from other sources, is applied either to compress a column of fluid or produce a
partial vacuum within a cylinder or cylinders on each carriage; or the said column or
other applianco is employed to regulate the closing up or opening out of said earringos
or of the train as a wholo with respect to the engine. The Iuvention is capable of
being applied in a variety of ways.
The accompanying Drawings exhibit several modes.
Figure 1 is a side elevation partly in section of two carriages fitted with my
improved brake appliance; Figure 2 is an end view of same; and Figure 3 is a
plan section through the lower part of the carriage.
Under each carriage a cylinder A is fitted containing a column of fluid, and
having a piston a at each end, and rods P, P, extending to both ends of carriage.
The buffers are connected by a cross bar or double lever S jointed to the piston rods,
or a spring may be used instead of the cross bar.
The brake cylinder (or cylinders) B is connected with the pressure cylinder A,
and may be placed under it or in any other suitable position; C is a pipe running
the whole length of the train, and is connected by the branch pipes a, a², a³, with
cylinder A of each carriage. On a² a valve opening inwards is fitted. Between
the cylinders, say at b, a double action valve is fitted (viz., a valve admitting
passage of fluid from A to B, and on being actuated from B to atmosphere), which
is actuated from either end of train by means of the pipe D. By the pipe C the
cylinders A and B are filled with fluid, say, compressed air on both sides of the
pistons. When the air in the cylinder A is further compressed by the closing up of
the carriages it is forced through be, and actuates the pistons 6 of the brake cylinder,
but is prevented from returning by the valve at b. The fluid displaced at the
back of the pistons in B passes through b¹ and 6 into cylinder A. On the guard
or engine driver opening a valve, say at g, and allowing compressed air to pass
from the pipe C to the pipe D the valve between the cylinders at 6 is actuated,
and a communication opened between the cylinder B and the atmosphere, the
pistons are forced towards one another by the expansion of the compressed air, and
the brakes taken off; or instead of the compressed air being allowed to pass to
atmosphere the valve at 6 may communicate with the branch pipes b' and 63, and
the pressure on each side of the pistons thus equalised. In this latter case tho
pistons will be closed by a spring.
According to a modified arrangement shewn at Figure 3a the cylinder A is con-
nected with the pipe C by branch pipes a¹ and a³, and with cylinder B by branch
pipes b, b, and 6. Compressed air is supplied to the cylinder A by the pipo D,
and branch pipes through the valve at e, and on the pipe b a simple valve fis
fitted to open and close the communication between the two cylinders, and to
be actuated through the pipe D. Compressed air is supplied to the B cylinder by
the pipe C and its branch pipes.
When the air in A cylinder is further compressed by the closing up of
carriages, it is forced through the pipe 6, and actuates the pistons of tho brako
cylinder. On the train of carriages opening out again by the engine being set on
the pistons in both cylinders return to their original position.

page_text: When the pipe D is filled with compressed air the valve at is closed, and the
carriages are prevented from closing upon one another, but on the pressure being
relieved either at the valve g or by accidental breakage of pipe the brakes can bo
applied. When both pipes are broken through the train dividing the brakes will
be instantly applied.
The valve at may be made to open a communication between cylinder B and
atmosphere when actuated as above described. In such case the brakes can not
only be put on but taken off from front or rear of train under any circumstances,
whether the engine brake is applied and the carriages close upon one another and
are in motion or not.
In Figure 4 is shown another arrangement, by which the buffers are made to
work in two cylinders A, A, in connection with one another, and with the central
or brake cylinder or cylinders B. On going round a curve the buffers on one side
will be as much compressed as the buffers on the other side will run out. In this
way as well as where a cross bar is employed complete case is given to the train,
and at the same time the carriages are more firmly attached to one another than
under the present system.
Figure 5 shows another arrangement. The compressed air is forced into the
cylinders A and B by the pipe D and branch pipes b1, b², b³. On b² a valve is fitted
opening inward, so as to thus ensure that the fluid pressure enters at the back of
pistons in cylinder B, that is, at b and b, earlier than between them, and thus the
brakes are taken off the wheels. Cylinder A is connected with the pipe C by the
branch pipes a¹ and a³ entering behind the pistons. In this case the fluid displaced
in cylinder B by the closing up of train passes by the pipe D through the
valve G, which may be on engine or brake vans at either or both ends of train,
into cylinder A by the pipe C and branch pipes a' and a entering behind the
pistons. Should the stop-cock at y be closed all displacement of fluid in B is
prevented, and so all action of the brake mechanism.
By the above mentioned arrangements the working of the continuous brake on
all ordinary occasions is provided for, as well as its instantaneous application in
cases of emergency. The continuous brake is governed by the hand brake on engine
or brake vans, and is thus completely under control of the engine-driver or guards.
In case of disruption of trains through any carriage running off the line each
carriage. in rear will have the brake applied with full effect. Where the train
becomes divided without leaving the rails it is evident that by the compressed air
escaping from the pipes C and D the cylinder B is also relieved, and the expansive
force of the air from cylinder A will instantly act upon the pistons of the brake
cylinder, and apply the brakes to each wheel in both portions of the train which
has become divided. This force can be applied to the brakes at the rear or in any
part of the train by the engine-driver in an emergency in addition to or instead of
his hand brake should the latter fail to act, or by the guard in rear should the
driver fail to notice a danger signal.
Figure 6 is a diagram of a plan in which water or any similar fluid may be used,
and in which no valves are necessary. The movement of displaced fluid is the
same as in Figure 5. To apply the brakes, in case of the train dividing without
leaving the rails, the piston rods of the brake cylinder are connected by a rope,
chain, or rod, with the adjoining carriages, so that in the act of disruption the
brakes of the foremost carriage of rear portion of the train may be applied and held
by any known mechanical means. Or the chain may be applied to the levers or
other part of the brake mechanism.
Figure Ca is a diagram of an arrangement wherein the compressed fluid from
cylinder A passes to the brake cylinder by either end of train instead of direct.
Figure 7 is a modification of Figure 1, in which water may be employed. Only
one piston of cylinder B is used to actuate the brakes, the other is attached to a
spring or used to compress air, so that an expansive force (as with nir) may be
ready for use on the train becoming divided.
A simple adaptation of this Invention, which may be fitted to the carriages at

page_text: present in use, is ullustrated by Figure 8. The ordinary buffers may be retained or
not, as thought desirable. One cylinder only is used with pistons at both ends and
piston rods running to the ends of the carriage, where they abut against or are
connected to tho piston rods from the adjoining carriages, or both abutting and
connected, as shown at Fig. 8. On each piston rod a spring is fixed, either inside
the cylinder, as here shown, or elsewhere, say at each end of carriage, which springs
force the pistons against one another. To the rods the two ends of a chain are attached.
On the pistons being porced towards one another the chain is tightened, the levers are
thereby actuated, and the brakes applied; or any other suitable appliance may be
substituted for chain. The cylinder H is connected by the branch pipes h', d', d³,
with the pipes C and D, and the fluid displaced passes by either or both ends of
train, from the front to the rear of the pistons, and vice versa, or the displaced fluid
may pass into a reservoir on engine or brake vans, in which case the use of the
pipe D may bo dispensed with. The engine-driver or guards, by opening or closing
the stop-cock g, regulate or altogether prevent the action of the brakes. In case of
the train becoming divided the pistons are closed by the springs and the breaks
applied. In using compressed air a reservo is to be kept behind the pistons,
also suitable valves on the branch pipes d', '; springs may then be dispensed
with.
In Figure 9 it is shown that the brakes may be applied either by the closing up
or opening out of the carriages of a train. On branch pipes H, H³, valves are
fixed opening outwards; in this case, when the train becomes divided and the
brake is applied at the rear of the train, the pistons are forced apart and the brakes
are actuated by means of the chain above mentioned, in the same way as if tho
pistons were forced towards one another.
Figures 10 and 10 shew a plan in which a single piston and cylinder H only aro
used with a rod attached running from end to end of carriage; this rod E, E, abuts
against or is connected to corresponding rods in adjoining carriages; in the former
case the brakes are taken off by springs. In this plan the carriages do not close
upon one another when the engine brake is applied, but the train of caninges closes
upon the engine or front brake van. The carriages at present commonly in use
may be employed without alteration of buffers. The buffer system as proposed and
described in Figures 1 and 2 may be used, or the buffers and connections may be
altogether omitted, a system adopted by several railway companies. Each carriage
may be fitted with a cylinder and one piston, or the engine only, or the brake vans
only may be 50 fitted. The two said singlo piston cylinders H may be respectivoly
connected by pipes running the whole length of train, with junction at either or
both ends. Or such pipes and connections between carriages may be dispensed
with, and the necessary connection between the two single piston cylinders formed
in each separate carriage. A chain or other appliance may be used to connect the
rods with the brake mechanism. The cylinders H are connected by branch pipes
with the pipes C and D (see Figure 10), on two of which c¹ and d³ valves are fitted
opening outwards, so that the piston may be held in proper position in centre of
cylinder when the rod is in tension. Or these branch pipes c and d and valvos
may be omitted, and instead thereof on each carriage, or on brake vans only, a bolt,
etud, or other appliance is fixed on piston rods to further the same object. When
tho position of the engine, with regard to the train, is reversed the position of the
bolt or stud will also have to be reversed. Upon the pipes C and D on each
carriage valves are fitted opening inwards. On the speed being checked on engino
the rods and pistons are forced backwards, and displace the compressed air in roar
of pistons which passes (see Figure 10) through branch pipes and D through the
valve g on engine to the front of piston in each cylinder; this movement of tho rod
applies the brake on each carriage. On the engine being again set on the fluid is forced
from the front to the rear of the pistons through branch pipes d³ and d', but as the
fluid in front cylinders cannot be displaced the pistons aro held in the centre of the
cylinder, and when in such position the brakes are off.
As regards the rear portion of train, should the train become divided the com

page_text: pressed air in cylinders at the back of pistons passes to the atmosphere by the
pipe D the expansion of the air on other side of pistons instantly puts on tho
brakes. On front portion of train this is reversed. The driver will thus have to
see that the valve at g is open, and apply his hand brake. The valves on the
branch pipes c and are made to close on the pressure being relieved in pipes.
Where the branch pipes c and d are omitted, as shewn at Figure 10ª, the pipes
Cand D are joined at end of train, and a valve is fixed there which closes on the
pressure becoming unequal in pipes C and D, that is, when the compressed air
escapes from the pipe D.
In Figure 10 the fluid in pipe C and D circulates by the front of train only; in
Figure 10 it makes a complete circuit in the pipes. In both cases the pipes and
cylinders being once filled with fluid, the action of the system of brakes will be
complete for any length of time, providing only for slight leakages at the joints.
This may be done by a small pump kept constantly going or automatically stopped
when the pressure is attained.
When the brake is applied on engine the carriages will close upon engine, but
it may also be applied in rear van, when the train will open out from engine. In
both cases the brakes of each carriage will be applied.
If the carriages are only connected by the piston rods, the train will open out
from rear van, and the continuous brake will be applied when the hand brake is
being used there, as well when the train is divided as when it is whole.
Should any carriage leave the rails, those in rear in closing upon it will have the
brake applied, and thus be prevented from telescoping into it or into one another.-
When water is used in cylinders the same objects are attained as with compressed
air, except when train is divided without leaving the rails. In this case the guard
in rear brake van would apply his hand brake, and (the piston rods being the only
connection) the brakes on each carriage would be applied.
Where the carriages are firmly attached without buffers the cylinders may be
omitted, except on the engine and in rear brake van; this applics in part also to
Figure 10a. A rope, chain, or pipe is then employed to actuate valve in rear van
when train becomes divided.
Instead of the cylinder and piston arrangement, a screw or other appliance may
be used to regulate the closing up or opening out of train, and its action on
brakes.
The screw may be applied as follows:-The rod under the brake van in front of
the train is made with a screw, which passing through the centre of a wheel causes
said wheel to revolve on the closing up (or opening out) of the train or from the
engine. This wheel is placed under control of the guard, who can by its means
allow or prevent the closing up or opening out of the train, and so any action of the
brakes; he can also facilitate either of these operations.
The connections between the carriages may be flexible or otherwise, as there is no
closing up of carriages upon one another.
It is evident that by changing the position of the branch pipes, having the valves
thereon to work automatically or otherwise increasing or diminishing their number,
and combining the plans as figured, many other modifications are possible, all more
or less important, but it seems unnecessary to describe them in detail.
The use of pipes and their connections may be dispensed with, in which case the
Buid must be put into the cylinder or cylinders of cach carriage separately by
means of a force pump on each carriage or otherwise, and a rope, wire, or chain led
along the train, by which the valve or valves may be actuated.
The buffers and connections, as in Figures 1 and 2, may be in all cases omitted;
nd in all the before-mentioned plans the piston rods may, by chains and pulleys,
be arranged so as to be in tension instead of in compression when actuated; or a
partial vacuum may be produced in cylinders, instead of or in addition to the com-
pression of fluid, by the closing up of the carriages.
The water or similar liquid fluid may be allowed to pass into the pipes and
cylinders by its own gravity, a small tap being fixed in a suitable position in each

page_text: carringefor escape of air, or a force pump may be used for this purpose to work
automatically from some moving part on engine or elsewhere. A three-way cock
or other similar valve is fixed on engine and brake vans, so that driver or guards
may apply the continuous brakes when required.
Referring to Figure 5 it will be seen that when the communication between the
pipes C and D is closed by the stop-cock g, the carriages can neither close up nor>
the brakes be applied. The train can then be backed. When the ongine brake is
on and the stop-cock partly open, the brakes will gradually be applied moro
rapidly when fully open instantaneously when the stop-cock is turned to relieve
the pressure in pipe D and in cylinder B. The communication between the pipes
being open through stop-cock the brakes are removed by the engine being set on.
In the other plans the saune objects are attained. The connections of the pipes C
and D between carriages may be flexible..
In the plans, Figures 1 and 7, the pipes and connections need only be of sufficient
size to admit of the cylinders being filled with fluid at intervals, and of the actua-
tion of small valves between cylinders. In the other plans it will be necessary that
the pipes and connections be large enough to admit of the required circulation of
fluid: Tho carriages may be attached to one another by the ordinary description
of couplings.
A plan is proposed of carrying the fluid through pipes with sliding joints, or
of making the buffer rods tubular, as shewn at Figure 13, and to encase an india-
rubber or other flexible tube throughout their length or only between carriages.
The pipes C and D have sliding joints at K, K, and may have ball-and-socket joints
at suitable part of the pipe, also be connected between carriages in a similar way
to piston rod shewn in Fig. 8°, so that there may be free play when the carriages
are in motion. India-rubber tubes are inserted into the metal pipes passing
through the ball-and-socket joints, thus proventing all leakage of fluid.
The pipes may be the buffer rods which are tubular, and an arrangement such
as this may be employed, or a short piece of strong india-rubber piping (with or
without a spiral spring) may be inserted through the buffer, and on the carriages
being screwed tightly up the india-rubber will be forced firmly into the neck of
the pipes. A littlo play will be given at the junction of the buffers.
For the purposes of train signalling and that the engine-driver may at once be
informed of any breakage of wheels, axles, or other portions of the machinery of
any carriage in the train, or of the cylinders, pipes, etc., in connection with the
brakes the pipe C is used, sec Figure 1, or the pipe D, see Figure 5. In a con-
venient position in each carriage and brake van a valve is placed, which may be
opened by any passenger or guard, allowing an escapo of fluid and causing an
inequality of pressure in the pipes, or a valve may be closed checking circulation
of fluid where such circulation is applied for heating purposes. In either case a
bell will be rung, or whistle sounded, on engine and wherever it may be desired.
Meanwhile, if the driver does not take more effective means of stopping the train
it will gradually be brought to a stand by the action of the continuous brakes.
Round cach axle and wheel a small branch pipe of metal is fixed. On the
breakage of either this pipe is also broken, an alarm is sounded on engine, and the
train, is stopped in the same way as with the passenger alarm. In Figures 11
and 12 are shewn the branch pipes in connection with the axles and wheels. The
pipe may pass partially round the wheel, as shewn, or across it.
Should the carriages be fitted with pipes for heating purposes a circulation of hot
water, air, or steam, can be established through the whole length of train. In
Figures 1 and 7 a pressure valve will be fixed at end of train to keep up the
pressure in the pipe C; in the other arrangements a valve to open with equal
pressures in the pipes C and D, closing when unequal.
.
And having thus fully described this Invention, I declare that I claim,--
First. Actuating continuous railway brakes by fluid pressure or vacuum columns
in pipes, the brakes being put into action when the carringes close up against one
another by the checking of the speed, as set forth.

page_text: Second. Actuating continuous railway. brakes by fluid pressure or vacuum, or
both, in cylinders; the said fluid being respectively compressed or attenuated when
the carriages close up against one another by the checking of the speed, as set
forth.
Third. Connecting the buffers to fluid-pressure cylinders arranged to actuate
continuous brakes, as set forth.
Fourth. Regulating the pressure on continuous brakes, as set forth.
Fifth. The arrangements, here described, for throwing the brakes out of gear
when the train is to be backed.
Sixth. The modes of and means for actuating continuous brakes, as more par-
ticularly here described and illustrated by the accompanying Drawings.
Seventh. The modes of and means for train signalling, as here described and as
illustrated by the accompanying Drawings.
In witness whereof, I, the said Alexander Gavin, have hereunto set my hand
and seal, this Second day of November, in the year of our Lord One thousand
eight hundred and seventy-six.
ALEX, GAVIN. (L.S.)