IMPROVE- MENTS IN COMPRESSED AIR BRAKES FOR RAILWAY TRAINS AND IN ENGINES FOR COMPRESSING AIR FOR THE SAME, WHICH ENGINES ARE ALSO APPLICABLE FOR OTHER PURPOSES
Year: 1875

page_text: LETTERS PATENT to James Steel, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVE-
MENTS IN COMPRESSED AIR BRAKES FOR RAILWAY TRAINS AND IN ENGINES
FOR COMPRESSING AIR FOR THE SAME, WHICH ENGINES ARE ALSO APPLICABLE
FOR OTHER PURPOSES
"
Scaled the 18th January 1876, and dated the 2nd August 1875.
PROVISIONAL SPECIFICATION left by the said James Steel at tho
Office of the Commissioners of Patents, with his Petition, on the
2nd August 1875.
I, JAMES STEEL, of Glasgow, in the County of Lanark, North Britain,
Engineer, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN COMPRESSED AIR BRAKES FOR RAILWAY TRAINS AND IN
ENGINES FOR COMPRESSING AIR FOR THE SAME, WHICH ENGINES ARE ALSO APPLI-
CABLE FOR OTHER PURPOSES," to be as follows, that is to say.
This Invention, which relates to improvements in compressed air

page_text: air used in actuating such brakes, consists as regards the biake apparatus
of a cylinder or chamber divided horizontally by an india-rubber, leather,
or other flexible elastic diaphragm The cylinder or chamber is
under one arrangement placed at the central part of the carriage frame,
and to the diaphragm therein the upper extremity of a rod extending
through the lower part of the cylinder is secured. The lower end of
the said rod is attached to lovers centred on studs fixed to the canage
frame, which levers are connected by rods or links to brake blocks,
preferably made of iron, and placed at both ends of the carriage, or
other equivalent means may be employed to connect the diaphragm to
the brake blocks. The chambers on the upper and under sides of the
diaphragm are of unequal capacity, that on the under side being the
greater. Compressed air is conducted into the upper chamber through
a pipe
and into the lower chamber through a branch, both of which arc
connected to the compressed air pipe extending throughout the length
of the train and communicating with the compressed air receiver.
the pipe first referred to an india-1ubber or other elastic valve is placed,
which is arranged to open upwards by the pressure of air bencath,
whilst back pressure on the upper side of the valve closes com-
munication with the compressed air pipe, and opens communication
with the atmosphere, or this action of the valve may be reversed. lu
the branch leading to the lower compartment of the brake c) linder a
⚫ valve is placed which is arranged to open only towards the said com-
partment By means of this arrangement of valves an equilibrium of
pressure is maintained in the upper and lower compartments of the
brake cylinder, which equilibrium, assisted by the weight of the brake
apparatus itself, keeps the brake blocks off the wheels
In
When the brakes are to be applied communication of the pipo
extending throughout the train with the compressed air receiver is cut
off. The pressure on the upper sides of the elastic valves herein-before
referred to then forces the valves downwards and opens communication
between the upper compartment of the brake cylinder and the atmo-
sphere. The pressure of air in the lower compartment then prepon-
derating forces the diaphragm upwards, and through the intervention of
the mechanism herein-before described applies the brakes.
Instead of placing one brake cylinder at the central part of cach
carriage frame, as herein-before described, a cylinder may be placed at
each end of the carriage, in which case the diaphragm is connected

page_text: to the brake blocks which act upon the wheels at the corresponding
end.
The diaphragm or piston rod of the brake cylinder may be packed or
rendered air-tight by an ordinary gland or modification thereof, but it is
preferred to pack the said rod by an clastic stocking placed over its
upper end, and secured by bolts passed through a flanch on the lower
end of the stocking and into or through the bottom of the cylinder.
The stocking is kept from contact with the piston rod by a spiral spring
or equivalent means
As regards improvements in engines for compressing air employed
in actuating compressed air brakes, this Tnvention consists in so
arranging such engines that the air is raised from atmospheric to any
desired degree of pressure by successive stages of compression
For
this purpose two or moic pumps are employed, and these are so arranged
relatively with each other that the air compressed to a predetermined
limit in the first pump passes therefrom into the barrel of the second
pump, wherein it is still further compressed. The air in this manner
may pass through any number of pumps until the required degree of
compression has been reached. From the last pump of the series the
air passes into the compressed air icceiver, and is from thence conducted
to the brake cylinders throughout the tram In connexion with cach
pump barrel a steam cylinder is provided, the piston of the cylinder and
plunger of the pump being situate on the same rod The slide valves
of the steam cylinders are actuated by eccentrics or equivalent gear
situate on a main shaft placed above, and whereon one or more fly
wheels are also secured, or instead of employing a main shaft a beam
may be used
The pumping engine is placed on any convenient part of the loco-
motive engine when employed in compressing air for actuating trai
brakes, but it is to be understood that besides being employed for this
purpose the engine may be used in pumping air, gas, or other fluids for
purposes generally wherein a pumping engine is employed, and instead
of placing the engine vertically as hercin-before described it may be
placed houzontally or at any desued angle.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Steel in the Great Seal Patent Office on
the 1st February 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
STEEL, of Glasgow, in the County of Lanark, North Britain, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of August, in the year
of our Lord One thousand eight hundred and seventy-five, in the
39th year of Her reign, did for Herself, Her heirs and successors,
give and grant unto me, the said James Steel, Her special license
that I, the said James Steel, my executors, administrators, and
assigns, or such others as I, the said James Steel, my executors,
administrators, or assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, usc, exercise, and
vend within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN COMPRESSED AIR BRAKES FOR RAILWAY TRAINS, AND IN ENGINES FOR COM-
PRESSING AIR FOR THE SAME, WHICH ENGINES ARE ALSO APPLICABLE FOR OTHER
PURPOSES," upon the condition (amongst others) that I, the said James
Steel, by an instrument in writing under my hand and scal, should
particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause
the same to be filed in the Great Scal Patent Office within sıx
calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said James Steel, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to
say.―
My said Invention which relates to improvements in compressed air
brakes for railway trains and in engines employed in compressing the
an used in actuating such brakes, consists as regards the brake apparatus

page_text: of a cylinder or chamber divided horizontally by an india-rubber, leather,
or other flexible or clastic diaphragm. To the diaphragm one end of a
rod extending downwards through the cylinder or chamber is attached,
the opposite end of the said rod being connected to cranks or equivalent
apparatus, by operating which the brake blocks are applied to and
released from the wheels of the several vehicles composing the train.
The air employed in actuating the brakes is raised from atmosplicric
to any desired degree of pressure previous to entering the bake
cylinders by the compressing engine constructed in accordance with
my said Invention, and which is herein-after described.
And in order that my said Invention may be properly understood,
I now proceed more particularly to set forth the system, mode, or
manner in or under which the same is or may be used or practically
carried into effect, reference being had to the annexed Sheets of
Drawings and to the letters and figures marked thereon, that is to
say.-
--
On Sheet 1 of the Drawings hereunto appended, Figure 1 is a vertical
section, and Figure 2 a plan of the brake apparatus constructed in
accordance with my said Invention, and as shewn thereon such apparatus
consists of a cylinder or chamber A, composed of an upper and lower
portion which are bolted together at the flanches B The upper part
of the cylinder or chamber is separated or divided from the lower part
by a horizontal diaphragm C, held in position by the flanches B, and
composed of india-rubber, leathor, or other equivalent material of a
flexible or clastic nature. On the upper side of the diaphragm C a plate
D of metal is preferably secured by bolts a passed through it, through
the diaphragm and through another plate E, situate on the under side
thereof as shewn at Figure 1, Sheet 1 The plate or disc D is employed
to prevent the diaphragm whilst in operation from bulging or assuming
a cuived figure, and also to afford means of attaching the rod F thereto,
which may
be effected by a screw tapped into the upper end of the rod
as shewn at b, Figure 1, or by other equivalent means. The rod F
passes through the bottom of the cylinder A, the hole or opening
through which the rod extends being packed or rendered air-tight by an
india-rubber or other flexible or elastic stocking G, which is drawn over
the lower end of the rod F, and is at its upper extremity attached to
the bottom of the cylinder A by means of screws or bolts c, which pass
through a ring or disc d of metal, and also through a flanch e formed

page_text: on the stocking as shewn at Figure 1, Sheet 1. A metallic coil f
is carried round the stocking G to prevent it from bulging outwards,
and the said stocking is kept from contact (at its vertical part) with the
rod F, by forming an annular space between them into which air under
pressure enters from the lower chamber of the cylinder A, or instead of ŏ
thus arrangement a spiral spring or other equivalent means may be
employed to prevent frictional contact of the said rod and stocking
Under another arrangement of packing the rod F, the stocking G
may be passed over its upper end and secured to the bottom of the
cylinder A inside the lower chamber thereof by screws or bolts in the 1
manner shewn, or instead of employing an elastic stocking for the
purpose set forth, the opening or passage in the cylinder for the rod F
may be rendered air-tight by an ordinary gland or a suitable modification
thercof.
The rod F, which for lightness may be cast or formed hollow as shewn, 1
is at its lower end attached to a jaw or fork H by means of a screw or
bolt, passed through the jaw or fork and in the arrangement shown
on the Drawings through the clastic stocking G and into the rod F,
but when the stocking is placed over the upper end of the rod, or when
an ordinary stuffing gland is employed, the said Jaw or fork in lieu of 2
being so attached is or may be formed on the rod F itself. A lever I is
centred on a pin or stud h, passed through the jaws of the fork II, the
said lever being connected by links to bell-crank levers J, or their
equivalents, which are centred on brackets K, attached to the framing
of the carriage and connected to the brake blocks by links M, portions 2
only of which are shown at Figure 1, Sheet 1 of the Drawings ;
The brake apparatus constructed in accordance with my said
Invention may be employed in two ways.
1
First one oulindon A may be tuned of the contures of the wailway.

page_text: of which two brake blocks preferably mado of iron are placed, that is
to say, a brake block for each wheel at the ends of the carriages.
Under the second mode of employing the brake apparatus, constituting
my said Invention, a cylinder A is situated at each end of the carriage,
and in this case the rod F is connected to one bell-crank lever J or its
equivalent, which by its links M is coupled to a cross bar carrying brake
blocks, whereby the wheels at the corresponding ends of the carriago
are braked when required.
Under both of these modes of employing my said Invention, air under
pressure is conducted into both chambers of each cylinder A (which
chambers as shown at Figure 1 are of unequal capacity) from the service
pipe N, extending throughout the train and communicating with the
air compressing engine on the locomotive. Into the upper and smaller
chamber the compressed air is conducted by a pipe O, communicating
with the pipe N, a branch P from the pipe O being connected to the
lower chamber of the cylinder A. In the pipe O an india-rubber or
other clastic relief valve mis placed, and which is arranged to open
downwards by the pressure of air in the valve chamber above it,
whilst back pressure from the upper chamber of the cylinder A on the
said valve has the effect, when the supply of air through the pipe N is
shut off, of closing the orifice o thereof and of raising the relici valve
from its seat o¹, whereby communication is effected between the
chamber above the diaphragm C and the chamber p, an opening in
which latter communicates with the atmosphere. A weight of lead
or other suitable material is placed at the interior of the india-rubber
valve m, to retain it on its seat and to keep it distended against the
interior of the chamber p, communication between which and the
chamber is at all times prevented by a ring of metal placed upon the
flanch at the upper side of the valve and held firmly in position by a
drop ring 8, which is pressed down upon it by the screwed covert of
the valve casing By means of this arrangement when the pressure' of
air through the pipe N is shut off, the relief valve being prevented from
rising bodily upwards by the ring s, has a tendency under the back
pressure to flatten itself at its lower part, whereby the india-rubber
becomes compressed and the passage downwards or upwards through
the valve is thus closed.
The action of the valve m may if desired be reversed, that is to say,

page_text: by pressure beneath, the closing of the passage through the valve being
in this also effected by back pressure from the chamber above the
diaphragm C, when the pressure beneath the valve is withdrawn
In the branch P leading into the chamber below the diaphragm an
equilibrium valve is placed and arranged to open only towards the said
compartment. By means of this system of valves a pressure of air is
maintained in the lower compartment of the cylinder A equal to that in
the upper compartment.
When the brakes are to be applied the pressure in the pipe N is
withdrawn, the pressure in the upper compartment of the cylinder A
then lifts the valve m from its seat o', whereby communication of the
said upper compartment with the atmosphere is effected through the
chamber p. The pressuro of air in the lower compartment of the
cylinder A then preponderating forces the diaphragm C upwards, as
shewn at Figure 1, and through the intervention of the mechanism :
herein-before described applies the brakes.
The releasing of the brakes is effected by restoring the pressure of air
in the upper compartment of the cylinder, the area of which is greater
than the area of the lower compartment by the sectional area of the
piston rod F, which greater area, together with the weight of the appa-
ratus depending from the said rod, constitutes the withdrawing or
relcasing force.
To permit of the carriages to which the brake apparatus is applied
being shunted or moved about when disconnected a cock or valve T is
provided for the withdrawal of the compressed air from the under side
of the diaphragm C, and the action of the brakes at such times is thereby
prevented. By opening the said cock or valve and closing the cock or
valve U in the pipe O the action of any set of the brake apparatus
throughout the train may be prevented as desired.
The different sections of the pipe N may be connected at the ends of
cach carriage, as shown on the Drawings appended to the Specification
filed in pursuance of the Letters Patent, No 623, AD 1875, hercin-
before referred to, or they may be connected by other suitable means.
As regards improvements in engines for compressing air employed in
actuating compressed air brakes my said Invention consists in so
arranging such engines that the air is raised from atmospheric to any

page_text: desired degree of pressure by successive stages of compression, and for
which purpose two or more pumps are employed.
On Sheet 2 of the annexed Drawings Figure 1 is a vertical section of
the compressing engine constructed in accordance with my said Inven-
tion; Figure 2 is a horizontal section of the same on the line a, b,
Figure 1, and Figure 3 an end clevation; whilst Figures 4 and 5 arc
respectively detailed views herein-after referred to.
The air-compressing engine shown by these Figures is situate upon
any convenient part of the locomotive engine or tender, and it consists
of two steam cylinders A, B, with their respective slide valves contained
within one valve chest and operated by eccentrics C on the shaft D, the
fly wheels or crank discs E, on which are connected to the piston rods F,
as shewn. The rods F of the steam cylinders are connected to the
pistons or plungers of the pump barrels G, H, the inlet and outlet valves
of which are arranged as shewn at Figure 4, Sheet 2, a separate set of
such valves being employed for the upward and downward strokes.
From the atmosphere the air passes into the pump G on both sides of
the piston or plunger by an inlet a, valve b, and branch c, the latter of
which is more particularly seen at Figure 5, which is a transverso
section on the line x, y, Figure 4. After being compressed within the
said pump to the desired limit the air passes outwards therefrom through
branches & and valves e into the pipe f connected to the pump II, and
into a branch g leading into a receiver J formed round the pump
barrel H. Tho air enters the pump II through the valve 2 and passage,
Figure 2, Sheet 2, which air after having been by the said pump II
further compressed to the desired limit passes outwards therefrom
through the branch k and valvo l, from whence it is conducted to a
compressed air receiver, and is from thence distributed throughout the
length of the train by the pipe N herein-before referred to and shown
on Sheet 1 of the Drawings. In this manner any desired number of
pump barrels may be employed, through which to pass the air until the
required degree of compression has been reached
Besides being used in compressing air for actuating continuous brakes
in railway trains as herein-before set forth, the compressing engine
3 constructed in accordance with my said Invention may be used in
pumping air, gas, or other fluids for purposes generally, wherein a
pumping engine is employed.

page_text: Figure 6 is a side elevation partly in section, and Figure 7 a horizontal
section of one form in which the improved compressing engine may be
arranged for general purposes, four compressing barrels or pumps A,
B, C, and D, respectively being shewn on 'the Figures referred to, the
plunger of each of which is connected to a crank on the shaft E placed
above, and which is rotated by the steam engines F, G, connected to the
fly wheels I placed thereon.
Instead of the shaft E a working beam or other equivalent motor may
be employed. The air compressed within the pumping barrel A passes
therefrom into a receiver I, and thence into the barrel B, from which,
after being further compressed, it passes into the receiver J, thence into
the barrel C, wherein a still further degree of pressure is reached before
the air passes into the receiver K, to be from thence conducted to the
pump D, and therein finally compressed to the desired limit before
passing away from the engine through the pipes L, or instead of this
arrangement the air vessels or receivers may be dispensed with and the
pump cylinders or barrels connected directly with each other.
Figure 8, Slicet 2, is a section of the pump A on the line a, b,
Figure 7, shewing the arrangement of the inlet and outlet valves which
are marked a and b, respectively The opening shewn in dotted lines
at c, Figure 8, is that through which the compressed air passes outwards
to the receiver in communication with the said pump, and also with the
inlet openings or branches of the next and higher compressing pump of
the series.
It is preferred that in the inlets through which the air first passes into
the pumping or compressing apparatus strainers should be placed, as
shewn at Figures 4 and 9, Sheet 2 of the Drawings
Instead of arranging either of the compressing engines herein-before
described vertically, as shewn on the Drawings, such engines may be
placed horizontally or at any desired angle, and when convenient and
where several pumping or compressing barrels are employed it is
preferred to place such baircls in a tank containing cold water, in
order to extract and absorb the heat generated in compressing air in the
manner set forth.
Having now described and particularly ascertained the nature of my
said Invention, and the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, I would observe

page_text: in conclusion that what I consider to be novel and original and therefore
claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,--
First The arrangement and construction of thic compressed air brake,
cylinder A, and apparatus in connexion therewith, where the action of
the compressed air ou opposite sides of an india-rubber or other clastic
diaphragm applies and releases the brakes to and from the wheels of the
vehicles composing a train, substantially as herein-before described with
reference to Sheet 1 of the accompanying Drawings
Second The india-rubber or other clastic packing G herein-before
described and shewn under one arrangement at Figure 1, Sheet 1 of the
Drawings, whereby the passage through the cylinder A for the
diaphragm rod F is rendered air-tight, substantially as set forth
Thud. The arrangement and construction of the compressing engines
herem-before described or any incre modification thereof, wherein air,
gases, or other fluids are raised to any desired degree of pressure by
succeeding stages of compression in the barrels of two or more pumps,
substantially as set forth and illustrated under two arrangements on
Sheet 2 of the Drawings hereunto annexed.
In witness whereof, I, the said James Steel, have hereunto set
my hand and seal, this Thirty-first day of January, One thousand
cight hundred and seventy-SIX.