Improvements in Valves for Air Brakes for Railway Vehicles and Similar Purposes.
Year: 1897

page_text: Date of Application, 20th Apr., 1897-Accepted, 21st Aug., 1897
Improvements in Valves for Air Brakes for Railway Vehicles and
Similar Purposes.
A communication from NIELS ANTON CHRISTENSEN, Mechanical Engineer, residing
at 465 Fourteenth Avenue, City of Milwaukee, County of Milwaukee, State
of Wisconsin, United States of America.
I, ALFRED JULIUS BOULT of 111 Hatton Garden in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention 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 "triple valves" so-called, employed in connection with
automatic air brakes.
Its main objects are to simplify the construction and improve the operation of
devices of this class, and it consists in certain novel features in the construction
and arrangement of the component parts of valve mechanism as hereinafter
particularly described and pointed out in the claims.
In the accompanying drawings like letters designate the same parts in the
several figures.
Fig. 1 is a vertical axial section of this improved valve on the line I, I, Fig. 2;
horizontal cross section on the line 3, 3, Fig. 1, and Fig. 4 a vertical cross section
on the line 4, 4, Fig. 1.
A designates the valve case. It is formed with a depending drip chamber a,
terminating at its lower end in a waste opening which is normally closed by a
screw plug or cap a¹. The drip chamber is formed on one side with a neck a²
provided with a coupling of any usual or suitable form for connection with the
train pipe. It is also formed inside, above and below the train pipe connection,
with inwardly projecting plates 3 and at, the upper plate serving to deflect into
the bottom of the chamber any dust, cinders or particles of dirt that may enter
through the train pipe; and the lower plate serving to prevent the air current
entering through the train pipe from disturbing the dust or dirt in the bottom of
said chamber.
The valve case is also formed in one end of the upper portion with a cylindrical
chamber as which may be designated the auxiliary valve chamber. This chamber
is closed at one end by a cap a blotted to the valve case with an interposed gasket
to prevent leakage. At the opposite end of this chamber a cylindrical extension a
of smaller diameter is formed concentrically therewith, and in the opposite end
of the case from the cap a is formed a chamber as which opens to the atomsphere
through a lateral passage a³, as shown in Fig. 4. Central cylindrical openings
of like diameter are formed in line with each other in the end of the valve case
towards the brake cylinder and in the partition between the extension a² of the
valve chamber a³ and the exhaust chamber a³. The cylindrical bushing forming

page_text: the main valve chamber C is snugly fitted in these openings and opens at one end
into the auxiliary valve chamber and at the other end communicates with the
auxiliary reservoir.
A passage all in the cap a connects the drip chamber a, and through it the
train pipe, with the outer end of the valve chamber as, a passage a leading out of
the opposite end of said valve chamber connects it with the auxiliary reservoir,
and a passage a leading from the end of the extension or opening a next to the
chamber as, connects it with the brake cylinder.
case.
In the upper part of the drip chamber a is formed a check valve chamber B
which has a port at its inner end opening into said drip chamber,
and a screw-threaded opening in its, outer end through the valve
Into this opening is screwed a barrel in which is loosely fitted a check valve 2
Dormally held by a spring against its seat in the port b. The chamber B opens
on the upper side into a passage, which "turn. communicates with opposite
sides of the opening a', as shown in Figs. 2 and 3.
The end of the valve case in which the passages a¹ and open, is formed, as
shown in Figs. 1 and 3, with a circular flange at for securing the valve to the
head of the brake cylinder. The train pipe, auxiliary reservoir and brake cylinder
connections are shown arranged according to the standard Westinghouse Air
Brake System so that this improved valve may be substituted for the triple valves
of that system without other change in the apparatus.
The main valve chamber C may be conveniently cast integrally with a
cylindrical bushing D which is fitted in the extension a of the auxiliary valve
chamber as, and is formed with passages d d and all opening at one end into
the valve chamber a5. At their opposite ends the passages open into an annular
enlargement of the passage a¹³, and the passages d' are closed, opening laterally
into the passage b₁.
d
Said valve chamber or bushing C is formed with two rows of radiating holes
or lateral ports c c¹ opening respectively into the exhaust chamber a8 in communi-
cation with the atmosphere, and into the annular enlargement of the passage a¹³,
in communication with the brake cylinder.
The main valve consists of the stem e formed or provided with two heads e¹
and fitted within the cylindrical chamber C, and normally including between
them, as shown in Fig. 1, the ports and c¹; and with a third head e controlling
communication between the main valve chamber and the auxiliary valve
chamber a as hereinafter explained. The head is exposed to auxiliary reservoir
pressure and thus balances the main valve. It is extended so as to prevent
communication between the exhaust port e and the auxiliary reservoir when the
valve is moved to the right.
F designates the auxiliary valve. It is made of annular form and is con-
structed and arranged to normally close the several ports of the passages d d
opening into chamber. Through the port or opening in its center passes the
steme of the main valve, and the head e normally closes said port or opening
thereby controlling communication between the auxiliary valve chamber and
the main valve chamber. The auxiliary valve is attached to the head of a
cylindrical extension g of the piston G which is fitted in a bushing g' of chamber a³.
The opposite end of this piston and its cylindrical extension is provided with a
perforated head or plate 2 through which air entering the chamber a³ from
passage a, enters the cylinder g. Within the cylinder g is fitted the piston E
on the main valve stem which is extended outwardly therefrom through the head g
of the auxiliary piston into a socket formed in the cap of the valve case.
The piston G is formed with wings ³ ³ by which it is guided and held in its
proper position in the bushing g'. A tubular plunger H fitted in the socket in
cap a and pressed inwardly by a spring against the piston head g², holds the
auxiliary valve F normally to its seat.
Openings are formed in the head of the cylinder to which the auxiliary
valve F is attached, and a space is left between said cylinder and the adjacent

page_text: end of bushing 1) so that there is free communication between that end of cylinder
and chamber a. The main valve chamber C is formed in one side between the
auxiliary valve F and the ports c¹ with a longitudinal passage by means of
which the supply of air from the auxiliary reservoir to the brake cylinder is gradu-
ated in making a service stop as hereinafter explained.
I have not shown in connection with this improved valve other parts of air
brake apparatus such as the auxiliary reservoir, brake cylinder and train pipe,
as their arrangement and operation are so familiar, and the illustration thereof
is not deemed essential to a clear understanding of this invention.
This improved valve operates as follows:
For making a service stop, pressure in the train pipe being reduced as usual,
say about five pounds, the piston E is moved to the right by the higher pressure to
which it is exposed on the opposite side from the auxiliary reservoir through the
passage a. This movement withdraws the head e' of the main valve from its
seat in the central opening or port of the auxiliary valve, and carries the head e
between the ports c and c', thereby cutting off communication between the brake
cylinder and the atmosphere through passage a, valve chamber C, chamber as
and passage a.
A further movement of the main valve in this direction carries
its head e over the passage, thus allowing compressed air from the auxiliary
reservoir to pass from the chamber a between piston E and auxiliary valve F
into the valve chamber C, through passage therein, around the head e¹, thence
through port c¹ and passage a into the brake cylinder. As the pressure in the
auxiliary reservoir approaches the reduced pressure in the train pipe, the piston E
will gradually move back to the left carrying the head e' of the main valve past
the end of passage ², thereby cutting off communication between the auxiliary
reservoir and the brake cylinder. A movement of the main valve to the left
sufficient only to carry the head el to the end of passage does not carry the
head far enough to open the port c. Consequently, if the piston and main
valve remain in this position the compressed air previously admitted to the brake
cylinder will be retained therein and the application of the brakes will be main-
tained as long as this condition continues. To release the brakes the pressure în
the train pipe is restored, thereby moving piston E and the main valve to its
original position, closing the port in the auxiliary valve F, and bringing the
perts c c into communication with each other, thereby allowing the compressed air
to cscape from the brake cylinder. By gradually lowering the pressure in the
train pipe a gradually increasing opening of the passage by the valve head el
will be produced, and a graduated admission of air from the auxiliary reservoir
to the brake cylinder will be effected. Thus a gradual application of the brakes
is made and any degree of pressure up to the maximum pressure may be applied
thereto and maintained when applied for any desired length of time by the proper
manipulation of the engineer's controlling valve. When normal pressure is
restored in the train pipe and the piston E is carried to the extreme limit of its
movement to the left against the reduced auxiliary reservoir pressure, the pressure
in said reservoir will be restored to normal by the passage of compressed air from
the end of cylinder G in communication with the train pipe, through a restricted
passage into the opposite end of said cylinder, thence through passage a¹ into
said reservoir. The passage, which is shown in Fig. 1, is closed by a slight
movement of the piston E to the right.
For making an emergency stop a greater reduction of train pipe pressure, say
about twelve pounds, is made in the usual way, whereupon the auxiliary reservoir
pressure will instantly shift both pistons E and G to the right, thereby not only
shifting the main valve so as to close communication between the exhaust port and
the passage 3 leading to the brake cylinder and establishing communication
between said passage and the auxiliary valve chamber a through the main valve
chamber C, but also unseating the auxiliary valve and opening the ports of the
passages d. When this takes place the air passing from the chamber a³ through
the passages dd, as well as through the main valve chamber C into the passage a¹³,

page_text: quickly reduces the pressure in the auxiliary valve chamber a below the reduced
train pipe pressure, whereupon the check valve 62 will open, allowing air from the
train pipe to pass through port b, passages and d into the auxiliary valve
chamber, thence through the passages d and passage a¹3 into the brake cylinder.
This further reduces the train pipe pressure and causes a like action of the triple
valves on succeeding cars to take place simultaneously or in very close succession.
The opening between the cylinder g and the adjacent end of the bushing D is of
smaller area than the ports of the passages d d so that upon the opening of the
auxiliary valve F for making an emergency application of the brakes, the passage
of air under higher pressure from the auxiliary reservoir will be restricted and
retarded so as to allow train pipe air under lower pressure to enter the brake
cylinder in the manner stated. As soon as the pressure in the brake cylinder
and train pipe are approximately equalized, the check valve 63 is closed by the
spring 63 after which air under higher pressure from the auxiliary reservoir will
continue to flow into and increase the pressure in the brake cylinder until the
pressure in said cylinder and reservoir are equalized and the most powerful
application of the brakes possible is made, which is effected almost instantly or in
a very short interval of time.
It will be observed that the passage in the valve case A and the passages & d
between the main valve chamber C and bushing D, constitute by-passages around
or outside of the main valve chamber from the train pipe and auxiliary reservoir
to the brake cylinder.
The restricted passage for the air from the auxiliary reservoir to the brake
cylinder for emergency application of the brakes, may be made by forming lateral
openings in the rim or flange of bushing D around or adjacent to the auxiliary
valve seat therein, said flange or rim in this case being fitted closely to the outer
rim of the auxiliary valve head. The passage in or through the main valve
chamber for effecting a service or graduated application of the brakes, may also
be variously modified. In place of a single passage as ², a number of similar
passages of the required area may be provided in the main valve chamber and so
arranged as to permit the passage of a gradually increasing volume of air as the
main valve is moved to the right.
In short, various modifications in the minor details of the device may be made
within the spirit and intended scope of this invention.
Having now particularly described and ascertained the nature of the said in-
vention as communicated to me by my foreign correspondent, and in what manner
the same is to be performed, I declare that what I claim is:-
1. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections, a main valve controlling
communication between the auxiliary reservoir and brake cylinder and
between said cylinder and the exhaust, a main piston for operating said
valve, exposed on one side to auxiliary reservoir pressure and on the
other to train pipe pressure, an auxiliary valve controlling communi-
cation between the train pipe and brake cylinder, and also between
the auxiliary reservoir and brake cylinder independently of the main valve, and
on auxiliary piston arranged to operate said auxiliary valve also exposed on one
side to auxiliary reservoir pressure and on the other to train pipe pressure, sub-
stantially as and for the purposes set forth.
2. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections and a waste or exhaust
opening, a main valve controlling communication between the auxiliary reservoir
and brake cylinder connections and between the brake cylinder connection and
exhaust opening, an auxiliary valve controlling communication between the train
pipe and brake cylinder, the main valve being movable independently of the
auxiliary valve, and main and auxiliary pistons one arranged to work within and
independently of the other and connected respectively with une main and

page_text: auxiliary valves, said pistons being exposed on one side to train pipe pressure and
on the other to auxiliary reservoir pressure, substantially as and for the purposes
set forth.
3. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections, a main valve chamber,
a main valve controlling communication through said chamber between the brake
cylinder and auxiliary reservoir and between said brake cylinder and
the atmosphere, a by-pass around said valve chamber for establishing
direct communication between the brake cylinder, train pipe and auxiliary reser-
voir independently of the main valve, an auxiliary valve controlling said by-pass,
and pistons connected with said valves and both exposed on one side to train pipe
pressure and on the other to auxiliary reservoir pressure, substantially as and for
the purposes set forth.
4. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections, an auxiliary valve
chamber having ports in communication with the train pipe and auxiliary reser-
voir, a main valve chamber open at one end into said auxiliary valve chamber
and having ports communicating with the brake cylinder and atmosphere,
by-passages outside of the main valve chamber having ports opening into the
auxiliary valve chamber and communicating respectively with the train pipe and
brake cylinder, an auxiliary valve normally closing the ports of said by-passages
and having an opening registering with
the open
end of the main
valve chamber, a main valve having heads normally closing the opening
in the auxiliary valve and controlling communication between the norts of the
main valve chamber, and pistons arranged in the auxiliary valve chamber between
the auxiliary reservoir and train pipe ports and connected respectively with said
valves, substantially as and for the purposes set forth.
5. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections, an auxiliary valve
chamber having ports communicating with the train pipe and auxiliary reservoir,
a main valve chamber opening at one end into said auxiliary valve chamber and
having ports communicating with the brake cylinder and with the atmosphere,
by-passages outside of the main valve chember and having ports opening into the
auxiliary valve chamber and communicating respectively with the train nipe and
brake cylinder, an auxiliary valve normally closing the ports of said by-passages
and having a port or opening registering with the opening in the end of the main
valve chamber, a main valve having heads normally closing the port in the auxiliary
valve and controlling communication between the ports of the main valve chamber,
a piston on the main valve stem which projects through the port in the auxiliary
valve, an auxiliary piston attached to the auxiliary valve and provided with a
cylindrical extension in which the main piston is fitted, said pistons being
arranged one within the other between the train pipe and auxiliary reservoir
ports of the auxiliary valve chamber, and a spring acting on the auxiliary piston
in opposition to the auxiliary reservoir pressure, substantially as and for the
purposes set forth.
6. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections, an auxiliary valve
chamber having ports communicating with the train pipe and auxiliary reservoir,
a main valve chamber opening at one end into said auxiliary valve chamber and
having ports communicating with the brake cylinder and with the atmosphere,
by-passages around or outside of the main valve chamber having ports opening
into the auxiliary valve chamber, and communicating respectively with the train
pipe and brake cylinder, a check valve in the by-passage between the train pipe
and auxiliary valve chamber, an auxiliary valve normally closing the ports of said
by-passages, a main valve controlling communication between the ports of the
main valve chamber and the admission of air to said chamber from the auxiliary
valve chamber, pistons arranged in the auxiliary valve chamber between

page_text: the
the train pipe and auxiliary reservoir ports and connected respectively
with the main and auxiliary valves, and a spring acting upon
auxiliary valve piston in opposition to the auxiliary reservoir pressure, the
main valve piston being movable independently of the auxiliary valve piston,
substantially as and for the purposes set forth.
7. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections, an auxiliary valve
chamber having ports in communication with the train pipe and auxiliary reser-
voir, a main valve chamber opening at one end into said auxiliary valve chamber
and having ports communicating with the brake cylinder and with the atmos-
phere, by-passages around or outside of the main valve chamber communicating
respectively with the train ripe and brake cylinder and having ports communicating
through a restricted opening with the auxiliary reservoir, an auxiliary valvo
normally closing the ports of said by-passages, a main valve controlling communi-
cation between the ports of the main valve chamber and the admission of air into
said chamber from the auxiliary valve chamber, and pistons connected with said
valves respectively and movable in the auxiliary valve chamber between its con-
noctions with the train pipe and auxiliary reservoir, the main valve piston being
movable independently of the auxiliary valve piston, substantially as and for the
purposes set forth.
8. In a triple valve for air brakes the combination of a valve case having train
pipe, auxiliary reservoir and brake cylinder connections, an auxiliary valve
chamber communicating with the train pipe and auxiliary reservoir, a main
valve chamber opening at one end in communication with the auxiliary valve
chamber, and having ports communicating with the brake cylinder and with the
atmosphere, by-passages around or outside of the main valve chamber having
ports opening into the auxiliary valve chamber and communicating respectively
with the train pipe and brake cylinder, an auxiliary valve normally closing the
ports of said by-passages, a main valve controlling communication through the
main valve chamber between the brake cylinder and auxiliary reservoir, and
between the brake cylinder and the atmosphere, and pistons arranged in the
auxiliary valve chamber between the train pine and auxiliary reservoir connections
and connected respectively with the main and auxiliary valves, substantially as
and for the purposes set forth.
9. The combination and arrangement of parts constituting the complete triple
valve for air brakes substantially as described and illustrated in the accompanying
drawings.