In- PROVEMENTS IN PNEUMATIC BRAKE AND INTERCOMMUNICATION SIGNALLING APPARATUS FOR KAILWAY TRAINS, PROAL SP
Year: 1875

page_text: LETTERS PATENT to George Westinghouse, junior, of Pittsburgh,
Pennsylvania, United States of America, at present of 115, Chancery
Lane, in the County of Middlesex, for the Invention of "In-
PROVEMENTS IN PNEUMATIC BRAKE AND INTERCOMMUNICATION SIGNALLING
APPARATUS FOR KAILWAY TRAINS,
PROVISIONAL SPECIFICATION left by the said George Westinghouse
at the Office of the Commissioners of Patents, with his Petition,
on the 3rd July 1875.
I, GEORGE WESTINGHOUSE, junior, of Pittsburgh, Pennsylvania,
United States of America, at present of 115, Chancery Lane, in the
County of Middlesex, do hereby declare the nature of the said In-
vention for "IMPROVEMENTS IN PNEUMATIC BRAKE AND INTERCOMMUNICATION
SIGNALLING APPARATUS FOR RAILWAY TRAINS," to be as follows:-
My Invention relates to valve devices whereby brakes are operated
automatically or otherwise, and signals are given between different

page_text: portions of a train. The said valves are operated by fluid pressure
(which may be the pressure of the atmosphere) and govern the flow
of the said actuating fluid to and from the brake cylinders.
The location and functions of the valve which is the subject of the
first of my Invention are substantially the same as those of the triple
valves, for which British Letters Patent were granted to me from 1872
onwards, and particularly during the years 1873 and 1874.
By preference one of the said valves is placed under each vehicle to
which it is desired to apply brake power, and communicates (A) with
a reservoir or accumulator, in which power is stored (B) with mechanism
for actuating the brake gear, such as a cylinder and piston or their
equivalent (C), with a main pipe or pipes extending the whole or part
of the length of the train.
When the operating fluid is employed at more than atmospheric
pressure the said main pipe or pipes is or are connected with a reservoir
or accumulator or direct to the exhaust part of a pump.
When atmospheric pressure is relied upon to apply the brakes the said
main pipe or pipes is or are exhausted and a partial vacuum maintained
by any suitable pump or by an ejector or ejectors operated by steam or
fluid. The said valve is operated and communication opened and
closed between the main pipe or pipes, the auxiliary reservoir, and the
brake cylinder, by means of the difference of pressure acting on both
sides of a piston working in a cylinder box or casing. The said piston
is provided with a stem fitted with a slide valve which works on a
suitable seat. As the piston moves backwards and forwards it opens
and closes a port leading from the main brake pipe or pipes to the
auxiliary reservoir or accumulator. From the slide valve portion of the
cylinder box or casing a port leads or opens to the brake cylinder; a
port which opens to the atmosphere is located beneath a cavity formed
in the face of the slide valve. The main pipe or pipes is or are in
communication with the outer end of the piston. The auxiliary
reservoir is in communication with the inner or valve and stem end of
the said piston.
When pressure is admitted to the valve box the piston moves so as to
open the port for charging the auxiliary reservoir, at the same time the
slide valve closes the port leading to the brake cylinder; the port.

page_text: leading from the brake cylinder to the atmosphere is however left open,
thereby releasing the brakes if previously applied. So soon as tho
pressure becomes equal on both sides of the piston all the ports are
closed by the action of springs. On a reduction of pressure taking
place in the main pipe or pipes communication between the brake
cylinder and the reservoir is opened, and the opening to the atmos-
phere closed, the brakes being thereby applied. A four-way cock
may if desired be fitted to or formed as part of the said valve. A leak-
age valve is also attached between the said valve and brake cylinder or
its equivalent.
Under the second part of my Invention, which consists in effecting
intercommunication signals, I arrange a signal valve to so open a port
in the main pipe or pipes that the reduction of pressure in the said pipe
or pipes by the outflow of air through the said port shall not cause a
greater flow of air from the reservoir to the brake cylinder than can
escape through the leakage valve. The flow of air from the main pipe
or pipes or through the leakage valve is caused to sound a whistle or
otherwise to signal. The said valves are fitted on, in, or to each
carriage, and are actuated by cords, levers, or equivalent means. When
the valve is once opened it is held open by the action of the escaping
air until a certain reduction of pressure has taken place in the main
pipe or pipes and the signal given, the said valve is then closed by a
spring. The said escaping air may also be caused to act on a piston so
as to throw out a semaphore or other signal.

page_text: our Lord One thousand eight hundred and seventy-five, in the thirty-
ninth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said George Westinghouse, junior, Her special
license that I, the said George Westinghouse, junior, my executors,
administrators, and assigns, or such others as I, the said George
Westinghouse, junior, my executors, administrators, and 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, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN PEUMATIC BRAKE AND INTER-
COMMUNICATION SIGNALLING APPARATUS FOR RAILWAY TRAINS,'
upon the
condition (amongst others) that I, the said George Westinghouse,
junior, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and scals, should par-
ticularly 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 six calendar
months next and immediately after the date of the said Letters
Patcnt.
دو
NOW KNOW YE, that I, the said George Westinghouse, junior, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
My Invention relates to valve devices used in the operation of brakes,
automatically or otherwise, and when signals are given between different
portions of a train, such as from passengers to driver and guards.
The valve device constituting the first part of my Invention is operated
by the difference of pressure of fluid; it may be the pressure of the
atmospere on the two sides of a piston, and serves to govern the flow
of the said actuating fluid to and from the brake cylinder or cylinders.
The location and functions of the said valves are substantially the
same as those of the triple valves for which Letters Patent were
granted to me from 1872 onwards, and particularly during the years.
1873 and 1874.

page_text: A valve constructed under this first part of my Invention consists
essentially of a piston and slide valve working in a chamber provided
with suitable ports or ways. In practice there are four ports or. ways.
One of such ports or ways leads from one side of the piston to a main
pipe connected from carriage to carriage throughout the train, in which
air under pressure or a partial vacuum is maintained by a pump, ejector,
or like means. A second port or way leads from the other side of the
piston to a supplementary or other reservoir. A third port controlled
by the slide valve leads to the brake cylinder or cylinders, and a fourth
port, also controlled by the slide valve, leads to the atmosphere.
.
1
Fig. 1 is a sectional view of a valve constructed under the said first
part of my Invention. a is the piston connected to the slide valve 6 by
the rod c, all contained in the chamber d; e, f, g, h, are the ports. The
port e leads from one end of the chamber d above the piston a to the
main pipe; the port f leads from the space i below the piston to the
reservoir or accumulator; the port under the slide valve leads to
the atmosphere; the port h, also under the slide valve, leads to the
brake operating cylinder. The cock j serves to disconnect the valve and
open direct communication from the main pipe to the brake operating
cylinder; the spring & serves to keep the piston in its normal position,
as shown.
If the pressure of air in the main pipe is greater than the pressure of
air in the supplementary reservoir the piston and slide valve move in
the direction of the arrow until the piston is seated at 7. The motion
given to the slide valve opens communication between the ports gandhi,
thus allowing any air in the brake cylinder above atmospheric pressure
to escape and relieve the brakes; at the same time air passes by the
ways m into the space i, and thence by the port f to the reservoir.
When the pressures on both sides of the piston become equal the
piston returns to its normal position and the slide valve closes the
ports and g.
:
"
I
:
If the pressure of air in the main pipe is less than in the reservoir to
such a degree as suffices to overcome the tension of the regulating
spring, the piston moves in the opposito direction to the arrow, until the
port is opened to the space i and air passes from the reservoir to the
cylinder and applies the brakes.
i

page_text: From the above description it will be obvious that to apply or release
the brakes it is only necessary to diminish or increase the pressure of air
in the main pipe.
Any leakage in the main pipe that would tend to apply the brakes is
compensated by a leakage valve, see Fig. 3, which is a view of the
bottom of part of a carriage looking upwards, where A is the valve;
B, the main pipe; C, the leakage valve interposed between the
reservoir D and the cylinder E. The operation and construction of
the said leakage valve has been fully described in my previous
Specifications. The said leakage valve also serves to prevent the
application of the brakes when the signal valve, hereafter described, is
operated.
When atmospheric pressure is relied upon to apply the brakes the
action is similar, except that when the port h is open to the space i a
vacuum is produced in the brake cylinder, and that when the ports g
and are in communication air passes from the atmosphere to the brake
cylinder.
Under the second part of my Invention, which relates to effecting
intercommunication signals on trains, I so arrange a signal valve to
open a port or escape way from the main pipe or pipes that the reduction
of pressure in the main pipe by the outflow of air through the said port
shall not cause a greater flow of air from any of the supplementary or
other reservoirs to the brake cylinders than can escape through the
leakage valves. The flow of air from the main pipe or pipes, or through
any one or more of the leakage valves, is caused to sound a whistle or
otherwise to signal. The said signal valves are fitted one on or to each
carriage, and are actuated by cords or levers or equivalent means.
When a valve is once operated it is held open by the action of the
escaping air until a certain reduction of pressure has taken place in the
main pipe or pipes and the signal given; the said valve is then closed by 3
a spring. I prefer that a whistle should be attached to the leakage
valve on the engine or tender so as to be near the driver; a whistle may
in like manner be connected to a leakage valve beneath the guard's
van. The escaping air may be caused to act on a piston so as to throw
out a semaphore or other signal, such as a ball attached to a cord or
chain.

page_text: Fig. 2 is a sectional view of a valve constructed under the second
part of my Invention. Here 1 is the valve casing; 2 is a way leading
to the main pipe; 3 is a way opening to the atmosphere; 4 is a valve
seating on 5 and kept in position by the spring 6; the seat 5 is pro-
longed cylindrically, and is surrounded by the jacket or sleeve 7, which
forms part of the valve 8. The lever 9 is connected by rods or a cord,
see Fig. 4, to a pull piece inside each compartment of a carriage.
When it is desired to give a signal the lever 9 is raised so as to lift
the valves 4 and 8, air then flows from the main pipe in the direction of
the arrows, through the openings 10, and up through the opening 11 in
the valve 8 to the atmosphere. When the pressure from the main pipe is
so far reduced that the force of upward flow of air through 11 is not
sufficient to overcome the downward pressure of the spring 6 the valves
close.
The reduction of pressure in the main pipe causes air to escape
through the leakage valves on each carriage, as explained under the
above first head. If a whistle F is attached to a leakage valve, as
shown in Fig. 5, a signal will be given. The leakage valve to which
the whistle is attached may be in any convenient position, or whistles
may be attached to more than one leakage valve.
A whistle may be
attached to the way 3, or the way 3 may be connected to a cylinder, as
shown in Fig. 6, the piston of which actuates the semaphores G. Instead
of a piston the cylinder may contain a ball connected to a chain; the
said ball will be blown out of the cylinder on a signal being given, and
will hang down and indicate from which carriage the signal has been
given.
Having now described the nature of my said Invention and par-
ticularized the same so that others will be enabled to carry my improve-
ments into effect, I claim,-
Under the first part:-(a.) The piston and valve, operating together
(b.) The piston a, port connections e, f, g, h, for the purposes set

page_text: Under the second part:-The intercommunication signal valve,
operating substantially in the manner and for the purposes set forth.
In witness whereof, I, the said George Westinghouse, junior,
have hereunto set my hand and seal, the Twentieth day of
December, in the year of our Lord One thousand eight hundred
and seventy-five.