IMPROVEMENTS IN PNEUMATIC RAILWAY BRAKES
Year: 1885

page_text: I JOHN HENRY JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of said Invention for "IMPROVEMENTS IN
PNEUMATIC RAILWAY BRAKES " which Invention has been communicated to me
from abroad by Léon Soulerin of Paris in the Republic of France Civil Engineer
to be as follows:-
This Invention relates to pneumatic apparatus employed for operating Railway
brakes and has for its main object to enable such apparatus to work with the same
power whether acted upon by compressed or by rarefied air or gas-The apparatus
may be arranged to work with a single main pipe running along the train, either
as plain vacuum brake, as an automatic vacuum brake or as an automatic com-
pressed air brake.
When employed with two main pipes, the apparatus may be made to act as a
duplex, plain or automatic vacuum brake, or as an automatic compressed air
brake,
In all cases a reservoir is provided for containing compressed air which reservoir
is connected to valvular apparatus by means of which the reservoir is made to
communicate (according to circumstances) either with the compressed air producing
apparatus or with a chamber containing a flexible diaphragm connected with the
brake block-The valvular apparatus is connected at one end to the main pipe and
is provided with a chamber containing a flexible diaphragm, secured at its periphery
to the chamber, and at its centre to a hollow spindle or rod containing a valve
which when the pressure in the main pipe is removed or released is acted upon by:
the pressure of the air in the reservoir so as to cut off the communication between
the main pipe and the said reservoir and thereby prevent the escape of the com-
pressed air contained therein-On a prolongation of the hollow rod or spindle is
another valve the object of which is (when acted upon by the compressed air) to
close the communication between the reservoir and the chamber containing the
flexible diaphragm connected with the brake block-When however the communi-
cation between the reservoir and the main pipe is stopped by the valve in the
hollow spindle the pressure of the compressed air, by acting upon the flexible
diaphragm to which it is connected, raises the hollow rod and removes the last
....מ

page_text: named valve from its seat and thus admits compressed air from the reservoir into
the chamber containing the flexible diaphragm connected with the brake block
against which diaphragm the compressed air acts so as to apply the brake-In the
passage leading to this diaphragm chamber is a pressure regulator consisting of a
valve connected to a flexible diaphragm the outer side of which diaphragm is open
to the atmosphere and is provided with a spring which tends to keep the valve
open to maintain a communication between the compressed air reservoir and the
chamber containing the brake diaphragm-This valve will remain open so long as
the pressure of the air upon the regulator diaphragm is not too great but so soon
as the pressure increases above the power of the spring the said spring will yield
and cause the valve carried by the diaphragm to, close and interrupt the passage of
air from the reservoir to the chamber containing the brake block diaphragm until
the pressure is reduced-The strength of the spring may be regulated as required
by means of a screw and nut or otherwise-Instead of the spring an air cushion
may be employed-The chamber containing the brake diaphragm is so constructed
that the spaces on the opposite sides of the diaphragm cannot communicate with
each other when the apparatus is at work except through an arrangement of valves
and passages communicating with the chamber on opposite side of the diaphragm
as bereinafter described.
The chamber is provided with release valves to be worked by hand when the
apparatus has worked automatically-The release valve in connection with the
space on that side of diaphragm to which the compressed air is admitted may be
arranged to act as a safety valve-The rod which connects the diaphragm to the
break block works through a stuffing box so constructed as to admit air from the
exterior to the interior of the chamber when necessary but will prevent air from
escaping therefrom.
For the purpose of enabling the brake to be applied by the power of a vacuum
the spaces on the opposite sides of the brake diaphragm communicate with a valve
chamber containing a duplex valve so arranged that when one of the valves of the
duplex valve is on its seat the other valve is removed from its-seat-This valve
chamber communicates by a pipe or passage with the main pipe.
In the normal position of the duplex valve (that is when pressure is removed
from the main pipe) the valve communicating with the main pipe is kept open and
the other maintained against its seat (by a spring) so as to cut off the communi-
cation between the opposite sides of the brake diaphragm-When however air
under pressure is admitted to the main pipe sufficient to overcome the power of the
spring the position of the duplex valve will be changed and the communication
between the valve box and the main pipe cut off whilst a communication will be
opened between the spaces on the opposite sides of the brake diaphragm.
In order to apply the brake air is exhausted from the main pipe thus causing
the diaphragm connected to the brake mechanism to rise in the chamber and apply
the brake and upon readmitting air to the main pipe the vacuum previously created
will be destroyed, and the air contained in the brake diaphragm chamber beneath
the diaphragm will escape through the valvular apparatus herein before described.
By slightly modifying the construction and arrangement of the compound valve
and combining therewith a vacuum reservoir the apparatus may be worked either
as an automatic vacuum brake or as an automatic compressed air brake.
In order to effect this, the valve spindle is connected to a flexible diaphragm
which is secured at its periphery to interior of the valve box and at its centre to the
valve spindle below a valve fitted to slide in or on the upper hollow end of the said
spindle. This valve in its normal position under the action of a spring is open and
establishes a communication between the main pipe and the vacuum reservoir
whilst another valve on the same spindle below the diaphragm closes the commu-
nication between the vacuum reservoir and the chamber containing the brake
diaphragm.
In the lower end of the valve box is fitted another valve which is provided on its
underside with a hollow cylindrical tail piece fitting a cylindrical opening formed

page_text: in the bottoin of the valve box. A notch is formed in a projection provided on the
upper side of this valve in which notch a peg or pin on the valve spindle may be
made to engage, when required, by means of a key introduced through the hollow
tail piece.
When the peg or pin is not engaged with the notch the valve is free to move
independently of the other valves carried on the spindle and will allow air to pass
from the brake diaphragm chamber above the diaphragm through passages in the
hollow tail piece. When however the peg is engaged with the valve it cannot open
except by the rising of the other valves and consequently no air can pass it from
the upper side of the brake diaphragm. When the brake is to be worked by com-
pressed air the peg is made to engage the valve, but when worked by vacuum it is
disengaged and air entering the hollow tail piece will raise the valve and allow the
air to pass into the valve box through passages provided in the tail piece below
the valve seat. Air is also admitted beneath the brake diaphragm through another
passage in the hollow tail piece.
The brake is kept out of action by maintaining a vacuum in the main pipe and
vacuum reservoir the valve on the upper end of the valve spindle above the
diaphragm herein before described being thereby maintained open and consequently
the communication between the brake diaphragm chamber and the vacuum
reservoir is cut off. In order to apply the brake, air is admitted to the main pipe
whereupon the valve on the upper end of the spindle will close and a communica-
tion between the vacuum reservoir and the brake diaphragm chamber above the
diaphragm will be established causing the said diaphragm to rise and apply the
brake.
When working by compressed air the valve in the bottom of the valve box is
engaged with the valve spindle by the notch and peg as herein before described and
so long as the brake is to be kept out of action pressure of air is maintained in the
main pipe when however the brake is to be applied pressure is removed from the
main pipe whereupon the valve spindle will be raised under the action of the spring
hereinbefore referred to and with it the valve in the bottom of the valve box,
thereby opening communications between the main pipe and the vacuum reservoir,
and between the brake diaphragm chamber above the diaphragm and the external
atmosphere through the passages in the hollow tail piece of the bottom valve.
whilst the communication between the brake diaphragm chamber beneath the
diaphragm and the external atmosphere will be cut off. The compressed air con-
tained in the compressed air reservoir hereinbefore described will then enter the
brake diaphragm chamber below the diaphragm causing it to rise and thus apply
the brake.
In order to take off the brake, pressure is again established in the main pipe.
By combining in one apparatus the two arrangements of compound valves herein-
before described and employing an additional main pipe so that each of the valvular
apparatus is connected with a separate main pipe the apparatus may be worked
either as a plain or automatic vacuum brake or as an automatic compressed-air
brake.

page_text: Improvements in Pneumatic Railway Brakes.
I JOHN HENRY JOHNSON of. 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this Invention which has been com-
municated to me froin abroad by Leon Soulerin of Paris in the Republic of France
Civil Engineer, and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
This Invention relates to pneumatic apparatus employed for operating Railway
brakes and has for its main object to enable such apparatus to work with the same
power whether acted upon by compressed or by rarefied air or gas and is intended
to be so combined as to fulfil either of the three following main requirements
videlicet.
No 1. To work with a single main pipe running along the train either as a plain
vacuum brake or as an automatic compressed air brake or
No 2. To be used also with a single main pipe either as an automatic vacuum
brake or as an automatic compressed air brake and
No 3. To be employed with two main pipes either as a duplex plain and
automatic vacuum brake or as an automatic compressed air brake.
And in order that the said Invention may be fully understood I shall now proceed
more particularly to describe the same and for that purpose shall refer to the
several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figures 1. 2 and 3 are sectional views representing respectively the combinations
for fulfilling the three requirements herein before enumerated.
In all these cases there is combined a compressed air reservoir R* a valvular
apparatus M a pressure regulator P and an enclosed space or a cylinder provided
with a moveable diaphragm or piston. The reservoir Rx is intended to store
compressed air for use whenever required and the valvular apparatus M is arranged
so as to cause the reservoir R* to communicate as required with either the
compressed air producing apparatus or with the space V* of the Vessel V V*
containing a flexible diaphragm n The valvular apparatus M contains a
diaphragm t connected to a hollow rod or spindle j through which compressed air
from the main pipe D is permitted to pass into the reservoir R*. In the rod j is
a valve p preferably spherical which whenever the pressure is released from the
main pipe closes the passage thereto so as to prevent the compressed air stored in
the reservoir R from escaping through the rod j into the pipe. On a prolongation
of this rod is another valve q which when acted upon by the spring and by the
pressure of the air in the reservoir R* closes the communication between the said
reservoir and the space V* Whenever the valve p closes the passage in the rod j
the spring yields to the pressure of the air contained in the Reservoir R* and the
valve q will be moved towards the main pipe by the pressure upon the diaphragm t
and whilst all connections are severed between the reservoir R* and the main pipe
the said reservoir is put in communication with the space V*
The pressure
regulator P is placed in the way of the air escaping from the reservoir R towards
the space V and consists of a flexible diaphragm q* which carries a valve h and

page_text: has its outer face in free communication with the ‘atmosphere, * is a spring the
tension of which is properly regulated by means of a screw x working in a
moveable nut y the object of this spring being to prevent the valve h from cutting
off the communication between the reservoir R* and the space V* as long as the
inner pressure is not too heavy upon the diaphragm q* should however the inner
pressure increase the spring will yield and the valve h will interrupt the flow.
of the air into the space Vx until the pressure has sufficiently decreased. An air
cushion may take the place of the spring * if desired. The vessel V V* can be
of any suitable shape the spaces V and V* being so arranged that they cannot.
communicate with each other nor with the exterior during the working of
the apparatus otherwise than through the working of valves as hereinafter
described. In both shells of the vessel V and Vx are release valves which are to
be worked by hands every time the apparatus has worked, automatically the
release valve of the space V* being so arranged to act in some cases like a safety
valve under the action of an internal pressure. A rod P* which acts upon the
brakes is attached to the diaphragm n n; it penetrates into the space V* through
a stuffing box so arranged as to allow whenever necessary the admission of
the external air pressure but to prevent the air contained in the space from
leaking out.
Figure 1 illustrates the arrangement for obtaining the requirements first
enumerated. D is the main pipe, R* P V V* and M are the parts herein before
referred to as forming part of each combination for obtaining the requirements.
enumerated. N is a duplex valve chamber.in which under the action of a spring
the valve b is pushed naturally against its seat so that when the space V and the
pipe D communicate all connection is severed between the spaces V'and V*
The
reverse takes place whenever a sufficient pressure is introduced in the pipe D as
shewn the spaces V and V× being in communication with each other and the
passage from the pipe D to the space V being closed.
To work the brake by vacuum power the parts in M and P and the rod P* will
remain in the positions shewn whilst the brakes are not applied, but in N the
tension of the spring will move the valves a and b so as to cause the space V to
communicate freely with the pipe D and cut off the communication between the
spaces V and V* Brakes may be applied by simply creating a vacuum in D
which will cause the diaphragm nn and the pendant rod Px to be lifted up and
the brakes may be removed by allowing the introduction of air into the pipe D;
the air contained in V* escaping through the valve q which can be raised with
a small effort thence through the hollow rod j into the pipe D the ball valve p
being sufficiently heavy as not to be moved by the slight pressures thus brought
upon it.
To work with compressed air the pressure in the pipe D is maintained when the
brakes are not to be applied the various parts of the apparatus assuming the
positions shewn in the figure the valves a and q being closed and preventing any
communication between the main pipe D and the spaces V and V* whilst
Compressed air will enter freely into the reservoir R*. By removing the pressure
in the pipe D the valves a and b contained in N will be raised by the spring and
thereby open a communication between the space V and the atmosphere through
the pipe D whilst the compressed air stored in the reservoir R* will cause the
valve p to rise and close the passage in the rod j leading to the pipe D; then the
diaphragm t will be raised and with it the valve q which being lifted from its seat
will allow the compressed air to rush through the pressure regulator P and
passage m into the space V* the regulator P acting as hereinbefore explained to
protect the apparatus from any injury due to overpressure. The compressed air
entering the space V* will cause the diaphragm n to rise and carry with it the
rod P and thus apply the brakes which will remain applied until compressed air is
reintroduced into the pipe D whereupon the various parts will be caused to resume
the position shewn in: the drawing, the spaces V and V* communicating freely
with each other and the brakes removed. .

page_text: A gradual application of the brakes may be obtained by reducing the pressure
in the main pipe D as required to any degree above the atmospheric pressure and
so that the difference of pressures in the spaces V and V* may be so adjusted that
the application of the brakes will take place slowly.
The re-introduction into the pipe D of a pressure at first slight but gradually
increasing will cause the brakes to be removed by degrees until the pressure will
have caused the duplex valve a, b, contained in N to close the communication'
between the space V and the pipe D and open the communication between the
spaces V and V* The safety valve placed in V* (but not shown in the drawing)
would allow air to escape whenever the inner pressure becomes too great.
Figure 2 is a Section of a slightly modified apparatus by which the requirements
herein before referred to as No 2 can be obtained. A represents a single main
pipe, R*, M, P P* and V V* parts similar to those described with reference to
Figure 1 and T a box containing a duplex valve of peculiar construction. This
valve consists of a flexible diaphragm y, y, to which is attached the spindle m*—
On the upper part of this spindle, which is hollow, rests a small valve a¹ kept
open by a spring .the object of said valve being to open or close as required,
communication between a vacuum reservoir R and the main pipe A.
There is also another valve b¹ the face of which is normally pressed against the
scat by a spring 8 which spring tends to maintain closed the communication
between the vacuum reservoir R and the space V-In the lower part of. the
chamber T is a valve g, provided at its lower side with a hollow tail piece or stem,
fitted to slide in a cylindrical passage bored or otherwise formed in the bottom of
the chamber T. The upper end of the valve g is provided with a projection having
a notch into which, is caused to engage a peg d, on the lower end of the stem or
spindle m* of the valve b the engagement being effected by means of a key
introduced into a square hole u in the stem or tail piece of the valve g-When
the peg d is not engaged with the notch, the valves 7 and 61 are free to work
independently. When however, the end of the stem m* is down in the cavity
of the upper stem of the valve g, then the said valve cannot be opened and
consequently no air can pass from the space V, to the atmosphere or "vice versa."
It is intended that the stem m* and the valve g, should be engaged only when
compressed air is to be employed as motive power, and they should be rendered
independent when working with a vacuum-Openings are provided around
and under the face of the valve g, which when the valve is raised off its seat admits
air to the chamber V, through the chamber T and passage ex. An opening O, in
the tail piece or stem of the valve g, establishes a communication between the
space Vx and the atmosphere through the passage c, when the valve g is on its
seat or is very slightly lifted above it-When, however, the valve g, is connected to
the stem m* when working by compressed air the tail piece or stein of the valve,
acting as a slide valve, opens and closes the communication between the space V*
and the atmosphere.
When working the apparatus with a vacuum the brakes are kept off by main-
taining in the pipe A, and reservoir R a vacuum which causes the valve a¹ to
remain open and the valve b' closed. Should the ball valve p be acted upon, then
the only effect would be to prevent the compressed air reservoir R* from communi-
cating with the pipe A. The brakes may be applied by admitting atmospheric
pressure into the pipe A, then the valve a will be closed. and the vacuum
reservoir R, will communicate with the space V, causing the diaphragm n to be
lifted and with it the rod P* and thus apply the brakes. The exhausting of the
air from the pipe A and the reservoir R, will cause the valve b to be lifted up, and
as the spindle m* is not attached to the valve g, the said valve will be only slightly
raised off its seat and only partly close the opening O, so that air will enter by the
passages u¹ and e* into the space V, whilst air from the space V* will escape
through the passages e and O, and allow the diaphragm n, and consequently the
rod P* to fall so as to take the brakes off,

page_text: When working the apparatus by compressed air the pressure is maintained in the
pipe A as long as the brakes are to be kept off, the several parts of the apparatus
remaining in the positions shewn in the drawing. In order to apply the brakes,
the pipe A is allowed to communicate with the atmosphere. The pressure thus
being removed the whole of the valves in the chamber T will be raised under the
action of the spring S and communication will be established between the space V
and the atmosphere, through the openings u¹¹ whilst the passage e will be closed
by the stem of the valve g, and consequently communication between the space V*,
and the atmosphere cut off. Compressed air stored in the reservoir Rx will now
enter the space Vx through the passage m, and raise the diaphragm n and rod Px
and thus apply the brake. In order to remove.the brakes, pressure is re-established
in the pipe A when the several parts will resume the positions shewn in the
drawing, the air contained in R will expand and enter the space V, the compressed
air contained in the space V* will flow into the atmosphere through the opening O,
and the diaphragm will fall and through the rod Px remove the brakes from the
wheels. The slightly rarefied air contained in the reservoir R and the space V will
be raised up to the natural atmospheric pressure when the brakes are applied.
A graduated application of the brakes may be obtained by re-introducing the
pressure into the pipe A before a certain quantity of the compressed air bas had
time to flow into the space Vx and by oscillations in manoeuvering a gradual
removal of the brakes may be effected.
Figure 3 illustrates an arrangement for obtaining the requirements hercinbefore
referred to as No 3, and represents the positions the various parts occupy when the
motive power used is compressed air and the brakes are off.-D is the plain brake
main pipe and A is the automatic main pipe; the parts R, R*, M, N, P, P*, V V*
and T, are the same as those already described with reference to figure 2, and the
part N, is similar to that described with reference to Figure 1, but is placed
between the chamber V Vx and the chamber T.
For working with a vacuum, the plain brake operates in the manner herein-
before described with reference to Figure 1 and the automatic brake like that
described with reference to Figure 2 and therefore require no further description
as the corresponding parts are indicated by corresponding letters in all the Figures.
For working with compressed air, the brake is operated, in the manner described
with reference to Figure 2, except that the communication between the space V,
and the atmosphere takes place through the valve a in the chamber N and the
main-pipe D. Compressed air introduced into the pipe D only causes the said
valve a, to rest on its seat and thus protect the diaphragm n from being acted upon
thereby.
Gradual application and removal of the brake may be obtained by admitting
into the pipe D more or less compressed air, so as to reduce as required the
difference of pressures in the spaces V and V*.
It is to be understood that in the combinations herein before described, more than
one chamber V, Vx may be placed on the same carriage, and may be otherwise
arranged than as shewn in the drawings, and the removing of the brakes may be
assisted by means of springs or otherwise if desired, also compound valves of any
suitable description may be used in place of those described.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is
First. In pneumatic Railway brakes, the combination, with a single main air pipe
extending along the train, of apparatus or means for working the brakes either by
a plain vacuum or automatically by compressed air substantially as herein before
described with reference to Figure 1 of the accompanying Drawings.
Second. In pneumatic Railway brakes the combination with a single main air
tube extending along the train of apparatus or means for working the brakes either
as an automatic vacuum brake or as an automatic compressed air brake substan-

page_text: tially as herein before described. with reference to Figure 2 of the accompanying
Drawings.
Third. In pneumatic Railway brakes the combination with two main air pipes
extending along the train of apparatus or means for working the brake either as a
duplex plain and automatic Vacuum brake or as an automatic compressed air brake
substantially as hereinbefore described with reference to Figure 3 of the accom-
panying Drawings.
Fourth. In pneumatic railway brakes the employment of apparatus or means
substantially as herein before described for enabling the brakes to be applied by
either compressed air or by vacuum at will the brake power being the same in
both cases as hereinbefore described.
Fifth. In combination with the subject matter of. the preceding claiming clauses
of a pressure regulator constructed and arranged to operate substantially in the
manner hereinbefore described and illustrated by the accompanying Drawings.
Dated this 10th day of December 1885,
"