Year: 1886

page_text: I, HERMAN HOLLERITH, residing at St. Louis, in the County of St. Louis, in the
State of Missouri, and United States of America, gentleman, 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:-
My invention relates particularly to that class of air brakes in which the valves
which govern the admission and exhaust of air to and from the brake cylinders of
the several cars, are controlled by electro magnetism.
In this class of air brakes, as heretofore constructed, it has been customary to
arrange the said inlet and exhaust valves so as to be capable of simultaneous
operation only, that is to say, upon the opening of the inlet valve, the exhaust
valve was closed and vice versa, the effect of this being to constantly hold the
brakes either fully on or entirely off.
In practice, however, it is found desirable to be able to control the brake
pressure or pressure in the brake cylinder more fully than is possible with the
arrangement of valves heretofore resorted to.
For instance, in descending long grades it is desirable to be able to apply the
brakes continuously under only a part of the pressure obtainable when the brakes
are fully on and also to be able to increase or diminish the pressure at will.
And while the variations of pressure in the brake cylinders are taking place it
is also desirable that the maximum pressure should be maintained, in the auxiliary
reservoir or power chamber, so that the full pressure of air may at any time be
instantly availed of in case of an emergency.
To accomplish this object I have devised a plan of construction whereby the
inlet and exhaust valves are rendered entirely independent of each other, and
capable of being operated either separately or together at will, so as to enable the
pressure in the brake cylinders to be either augmented or reduced without
changing the pressure in the auxiliary reservoir and main air pipe and thus
putting the brakes under complete control.
In carrying out this part of my invention, I employ two electric circuits, or one
current divided into two branches extending throughout the train, and I arrange in
one circuit or branch the electro magnets which control the inlet valves and in the
other circuit or branch the electro magnets which control the exhaust valves, and

page_text: I provide means whereby the said circuits or branches, or either of them, may be
broken or closed at will, so as to apply or release the brakes, or adjust and control
their pressure and I arrange the circuits so that when broken or interrupted from
any cause, such for instance as the separation of one or more cars from the body of
the train, the brakes will be applied.
I also provide means whereby, when from any cause the pressure of air in the
supply pipes falls below a certain safe limit the electric circuit will be broken, and
the brakes applied, and, if desired, the pressure in the main reservoir maintained,
all as will be hereinafter described.
In the accompanying drawings:
Figure 1, is a diagram, illustrating the application of my invention to a railway
train, the inlet valves being shown closed and the exhaust valves open.
Figure 2, is a view illustrating the position of the inlet and exhaust valves,
when the former is open and the latter closed.
Figure 3, is another view showing both the inlet and exhaust valves closed.
Figure 4, is a plan view of one of the valve chambers which I prefer to use.
Figure 5, is a side view of the same.
Figures 6 and 7, are vertical sections taken on the lines x-x and y-y respec-
tively, figure 5.
Figure 8, is a horizontal section taken on the line -z, figures 6 and 7.
Figure 9, is a horizontal section taken on the line w-w, figure 5.
Figure 10, represents a longitudinal vertical sectional view of one of the devices
by the operation of which the electric circuit is broken when the pressure in the
air supply pipe fails or falls below a predetermined point.
Figure 11, is a sectional view taken on the line u-u, figure 10.
Figure 12, is a cross sectional view of another form of automatic circuit
breaking device and valve for checking the discharge of air from the main
reservoir.
Figure 13, is a sectional view taken on the line vv, figure 12.
Figure 14, a sectional view taken on the line t-t, figure 12 and,
Figure 15, a section on line 7, figure 14.
In the diagram, figure 1, A, represents the main air pipe extending throughout
the train, B, branch pipes leading to auxiliary reservoirs C, located one on
each car.
D, are the brake cylinders having pistons connected to the brake levers in the
usual manner.
E, are the valve chambers located between the auxiliary reservoirs and the brake
cylinders.
The preferred construction of these valve chambers and their contents is shown
in figures 4 to 9 inclusive.
They each contain a tubular inlet valve F, and a similarly formed exhaust
valve, G.
Both of these valves, at their lower ends, open into a small chamber E, from
which leads a pipe I, to the brake cylinder, while at their upper ends they open
respectively into small independent chambers J and K, the former communicating
with the auxiliary or power reservoir, and the latter with the open air.
The upper end of the inlet valve, and the lower end of the exhaust valve are
each brought to an edge, and are adapted to seat against soft rubber gasket L, so
as to form tight joints therewith.
Perforations M, are made in the casing or wall back of these gaskets, in order
to permit the escape of air that might leak behind the latter; and suitable
packings N, are provided to prevent the escape of any air into the interior of
the chambers.
By constructing the upper and lower chambers very small, they are enabled to
withstand great pressure without being made very heavy, and as these chambers
are the only part subjected to pressure, the whole valve casing is therefore enabled,
to be made light.

page_text: The valves, it will be observed, are nearly perfectly balanced, the only resistance
to their operation being due to the friction of their packing rings.
Upon each valve is formed or secured a stop or collar O, between which and the
casing a spring P, is arranged for the purpose of ensuring the proper descent of the
valves when released.
In the large interior compartment of each valve chamber are arranged electro
magnets Q, and R, each of which is supported by a screw S, and adjusted by
screws T, T.
Below the electro magnet Q, is arranged an armature U, which is pivoted at V,
and has its outer end bifurcated so as to embrace the inlet valve T, below an
adjustable stop or collar W, arranged thereon, as shown in figure 6.
A similar armature X, is arranged below the electro magnets R, and is adapted
in like manner to operate the exhaust valve G, as shown in figure 7.
All the electro magnets which control the inlet valves are included in one
electric circuit and all the electro magnets which control the outlet valves are
included in another circuit, thus rendering each set of electro magnets and valves
independently controllable."
Various ways of arranging these circuits may be resorted to.
In the arrangement shown in figure 1, a circuit extending from an electric
battery or other electrical generator A, located upon the engine is divided at A³,
into two insulated branches A', A³, which pass through the main air pipe
extending throughout the train, all the electro magnets controlling the inlet valves
being looped into the branch A, and all those controlling the exhaust valves being
looped into the branch A5, and the main air pipe itself serving as a return to the
battery as will be readily understood.
The ordinary couplings and electrical connections are employed between the cars,
and need no particular description.
Upon the engine is located any suitable arrangement for opening and closing
the branch A, at the point A, and for opening and closing the branch A, at the
point A'.
Normally both branches of the circuit remain closed this causing all the inlet,
valves to be kept raised against their seats and the exhaust valves to be kept
raised from their seats as shown in figure, 1, thus cutting off all communication
between the compressed air supply and the brake cylinders, & putting the latter
into communication with the open air.
If not both branch circuits A4, A5, be broken at A, A7, all the inlet and exhaust
valves will drop, as shown in figure 2, and allow the compressed air to rush down
through the inlet valves into the lower chamber H, and thence into the brake
cylinders and cause the brakes to be applied.
While the brakes are still on, the branch A', may again be closed which will
seat all the inlet valves and cut off communication with the auxiliary reservoirs,
but yet retain the pressure in the brake cylinders.
Should it be desired to keep the brakes on a considerable length of time as in
coming down a grade and should the brakes relax their hold through leakage of
air from the brake cylinders the pressure in the latter may be augmented by again
breaking the branch circuit A, and thus opening again the inlet valves, and then
making the circuit again to close them.
'
On the other hand, should it be desired to release the brakes or to relax their
pressure, merely, it may be done by closing the branch A³, so as to
for a
open,
longer or shorter time, the exhaust valves, and allow the whole or a portion of the .
compressed air to escape from the brake cylinders the inlet valves being meanwhile
kept closed.
By breaking and closing both branches of the circuit, simultaneously, the opening
of all the inlet valves, and the closing of all the exhaust valves may be effected:
simultaneously and vice versa.
It will thus be seen, that, by my invention, all the valves are kept under the-
most perfect control, the inlet valves independently of the exhaust valves, and that,

page_text: therefore, the brakes of each car are susceptible of being manipulated to the best
advantage and simultaneously with the brakes of all the other cars in the train.
The arrangement is also such, that should the circuits be broken, as by the
parting of the conductors between cars or at any other point, or should the current
flowing stop or fall below normal strength the armatures will be released, the inlet
valves opened, the exhaust valves closed and the brakes applied to each car or at
least to such cars as become detached from the body of the train.
It is obvious that should the pressure in the main pipe fall below the prede-
termined limit or be removed entirely by a break in it, or a dis-arrangement of the
air compressing apparatus, serious results might follow, since the engineer, after
drawing on the supply of air in the auxiliary reservoirs until exhausted, would
loose all control of the brakes.
To avoid the possibility of such an occurrence I therefore arrange in the main
circuit one or more electric switches or circuit breaking devices connected with and
operated by a small piston arranged in the main air pipe and actuated in one
direction by the tension of a spring or equivalent tending to break the circuit and
in the other direction by the pressure of air in said main pipe to keep the circuit
closed.
When the pressure falls below the predetermined limit the spring forces the
piston down thereby operating the electric switch, breaking the circuit and
applying the brakes.
These circuit breaking valves may be of various forms:-
In the arrangement shown in figures 1, 10, and 11, a chamber B², is coupled to
the main air pipe so as to practically form a portion of the same, and up into this
chamber extend the several ends of a conductor C, which is in electrical connection,
at D, with the air pipe, and forms with the said pipe the return circuit to the
battery or other current generator.
These severed ends are in turn electrically connected with contact fingers E²,
which in turn are adapted to bear either upon the ebonite portion F, or upon the
metallic portion G³, of the piston H2, adapted to play in the upper part of the
chamber as shown.
This piston has arranged behind or above it a suitable spring I2, which tends to
force it inward.
When the pressure of air in the air pipe is at or above normal, the piston is
forced up and held against a flange J*, thus causing the metallic portion G³, to be
interposed between the metallic fingers E³, and establish the circuit, but, when,
from any cause, the pressure in the air pipe falls below normal the spring I, will
assert itself and force the piston inward so as to interpose its ebonite or insulated
portion between the metallic contact fingers, and thus break the circuit and cause
the brakes to be applied.
The strength of the spring is regulated so as to move the piston at any pre-
determined degree of pressure within the pipe.
In the construction illustrated in figures 12, 13, 14, and 15, I use a loaded
piston which is actuated by the difference of pressure in the main reservoir and
main pipe and which is connected with and operates an electric switch or circuit
breaker controlling the main electric circuits and a valve controlling communication
from the main reservoir to main air pipe; the whole being so arranged that when
there is any unusual or sudden diminution of pressure in the main air pipe, as in
case of breakage of same, the piston will operate to break the electric circuits and
close the valve thus checking further discharge of air from the main reservoir.
The piston, however, being loaded (by spring) will not operate when pressure is
diminished gradually as in the ordinary operation of the brakes.
Referring to said last mentioned figures, K2, represents a shell or casing
interposed in the main air pipe and divided by a diaphragm or partition L³, into
two compartments M, N, the pipe leading from the main air reservoir leading
into the former, and the pipe conveying the air to the train, leading out of the
latter.

page_text: A port O, which may be of cruciform shape, is made in the diaphragm L², and
through this port plays a valve stem P2, bearing near its lower end a valve Q',
provided at its upper end with a piston S2, which is fitted to the bore of the
compartment N³, and has bearing upon it a spring T2.
A pipe U, leads out from the upper compartment above the piston S', another
pipe V, leads from the said compartment below the piston, while still another
pipe W2, leads from the lower compartiment N2, all three of said pipes centering at
and coupled to a coupling X, in which a three way cock Y2, is arranged.
To the lower end of the valve stem P, is secured a projection A2, of ebonite, or
some other insulating material, carrying one or more rings or bands of metal B³,
and with this ebonite projection and its bands are adapted to cooperate one or
more pairs of spring contact fingers, and four circuit wires, this being the necessary
equipment where a return wire for each circuit is provided, and where all the wires
are to be ruptured: but where only one wire forms, with the pipe itself, the return
circuit, as shown in figure, 1, only one wire and one pair of contact fingers will be
required.
Normally the three way cock Y*, stands open, as shown in figure 12, so as to
put the upper part of the compartment, M³, above the piston, and the lower
compartment N2, into communication, and cause the air pressure on both sides of the
piston S², and valve Q, to be equal.
Thus air balanced, the spring T2, asserts itself and causes the piston to descend
so as to bring the metallic rings B³, into contact with the spring contact fingers,
and thus keep the circuit closed.
Should now, a break occur in the main air pipe, the sudden reduction of pressure
in the lower compartment N³, and in the upper part of the upper chamber M2,
would cause the pressure in the lower part of the upper compartment M2, below
the piston, to preponderate and the piston, by reason of its large area, would be
forced up, thus breaking the circuit by the interposition of the ebonite between the
contact fingers and at the same time seating the valve Q2, on its seat R, thereby
holding the air pressure in the main reservoir.
Pressure may be again established in the main air pipe throughout the train, by
turning the three way cock Y³, so as to put the upper and lower parts of the upper
compartment M³, above and below the piston, into communication, whereupon the
piston will be again air balanced and the spring allowed to assert itself, force down
the piston and again close the circuits.
Another embodiment of my invention is shown in figures 16 to 22, inclusive,
of which,―
Figure 16, represents a diagram of so much of the equipment of an engine, and
one car of a train as is necessary to show the application of my invention.
The
valve controlling the inlet of compressed air to the brake cylinder, of the car being
shown closed and the valve controlling the exhaustion of air from said brake
cylinder being shown open so as to put the cylinder in communication with the
open air.
Figure 17, is a view showing the position of the various parts when the brakes
are on, the inlet valve open and the exhaust valve closed.
Figure 18, a view showing the position of the parts when the brakes are on and
both the inlet and exhaust valves closed.
Figure 19, represents a modification of the arrangement shown in figure 16.
Figure 20, shows a practical mode of enclosing or boxing the several relays
employed in the construction shown in figure 16.
Figure 21, is a view of the switch or current reverser employed for manipulating
the current so as to cause it to flow in either direction or be interrupted entirely.
Figure 22, is an end view of the same.
A, represents the main air pipe through which the air compressed and forced
into it at the engine is conveyed throughout the train.
B, the branch pipe leading from said main pipe into
D, is the check valve in the auxiliary reservoir C.
the auxiliary reservoir C.
E, is the valve casing

page_text: containing the tubular inlet valve F, & the tubular exhaust valve G. The upper
ends of said valve F, operates within a small chamber e, which is in communication,
through a pipe f, with the auxiliary reservoir and the upper end of the exhaust
valve G, operates within another small chamber e¹, which is in communication
with the open air while the lower ends of both said valves operate within small
chambers e², e, in communication with each other & with the brake cylinder H,
through a pipe h.
The inlet valve F, seats upward while the exhaust valve G, seats downward
and each is provided with suitable packings i, to prevent the passage of air from
the upper to the lower chamber in which they respectively operate save .down
through the valves themselves when the latter are shifted to the proper positions.
The piston in the brake cylinder is connected to the brake levers in the usual
manner.
Upon the engine is mounted a suitable current generator I, preferably consisting
of a compound dynamo electric machine (such as used in connection with
incandescent lamp circuits) which regulates the current according to the external
resistance.
The current conducting wires from this dynamo extend to a suitable current
reverser such for instance as that shown in figure 21, wherein one wire designated
is connected to a contact finger 1, and the other wire designated + is connected
to a contact finger 2, while the outgoing circuit wire W, is connected to a contact
finger 3, and the return wire W, to a contact finger 4.
The ends of all these contact fingers are adapted to bear upon a cylinder J, the
body of which is of insulating material but has metallic conducting portions 5, 5,
6, and 7.
When the cylinder is turned so as to bring the fingers 2, 3, upon one metal
surface 5, and the fingers upon the other metal surface 5, what may be termed a
direct current will be sent through the circuit in the direction indicated by the full
line arrows in figure 16, but when the cylinder is turned so as to bring the
fingers 2, 4, upon the metal surface 6, and the contact fingers 1, 3, upon the metal
surface 7, the current will be reversed and will flow in the direction indicated by
the dotted arrows in figure 16, and when all of said contact fingers bear upon the
insulated portion of the cylinder the circuit is broken and no current at all passes.
It is designed that this current reversing apparatus or any other which may be
substituted for it shall be arranged upon the engine in convenient position to be
operated by the Engineer and enable him to control the current.
Interposed in the outgoing portion W, of the circuit on each car are two
relays R, R¹, the armatures 81, of which form part of a branch circuit T, which
also includes the coils of a polarized relay and an electro-magnet M, which controls
through an armature m, the inlet valve F, of the air brake apparatus.
Another branch circuit V, includes the armature w, of the polarized relay and
an electro-magnet M³, which controls through an armature m³, the exhaust
valve G, of said air brake apparatus.
The circuit W, W2, extends throughout the train and consists of insulated wires
carried through the main air pipes and suitably coupled between the cars or the
outgoing wire may be passed through the air pipe and the air pipe itself or the
track used as a return conductor the arrangement of the conductors being a matter
purely arbitrary.
It should be understood that each car of the train is provided with the valve
magnets and relays arranged in multiple arc as shown in figure 16, a suitable
resistance being interposed between the outgoing and return conductors at the rear
of the last car of the train as shown at O, figure 16, for the purpose of preventing
short circuiting of the battery when the relays have closed the branch circuits.
Normally the switch or current reverser is turned into the position shown in
figure 21, which maintains a direct current in the circuit causes both the branch
circuits T and V, to be closed and electro magnets M, M³, arranged therein to

page_text: close the inlet valves and open the exhaust valves thus keeping the brakes off as
shown in figure 16.
To apply the brakes it will only be necessary to break the circuit by means of
the switch or current reverser S, located at the engine or by the rupture of the
circuit at any point by the conductor, a circuit breaker such as shown at P, being
preferably arranged upon each car for this purpose.
The instant the circuit is broken, the magnets controlling both the inlet and
exhaust valves on all the cars of the train, instantly release said valve, and they
drop into the position shown in figure 17, the inlet valves being opened and the
exhaust valves seated, thereby permitting the compressed air to rush into the brake
cylinders and apply the brakes.
When a sufficient pressure has been obtained in the brake cylinders and it is
desired to retain said pressure therein, the switch or current reverser is turned by
the engineer into the position which will bring the contact fingers upon the metal
portions 6 and 7, and close the circuit W, W, again, but cause a reverse current
to flow through it in the direction indicated by the dotted arrows in figures 16,
and 18.
This reversed current will pass through the branch circuits T, and, by energizing
the electro magnets M, therein, will close the inlet valves, but the polarized
armatures forming parts of the circuits V, will be shifted towards the opposite
poles of their respective magnets, causing the demagnetization of the magnets M²,
by the interruption of the current and, consequently, allowing the exhaust valves
to remain closed.
If it is desired to augment the pressure in the brake cylinders, without entirely
releasing the brakes for the purpose of compensating for the leakage of air from
said cylinder, as for instance in coming down a long grade, where it is essential
that the brakes be kept on more or less the whole time, it can be accomplished by
the opening and closing of the circuit by the switch apparatus, with the reversed
current still on, which will open and then close the inlet valves and permit
additional compressed air to enter the brake cylinders and to be confined therein,
the exhaust valve mean while remaining closed.
By the provision of the two relays R and R¹, upon each car, a rupture of the
circuit upon each car, and the consequent application of the brakes is caused,
whenever any one or more of the cars become detached from the train, and whether
the current generator be at one end of the train or the other, such breaking of the
circuit, and application of brakes, occurring as well upon the body of the train as
upon the car or cars detached therefrom; for instance, should the rupture of the
circuit occur on one side of said relays, as at N, figure 16, both relays R and R¹,
would be demagnetized and their armatures would leave their contacts 84, 8³, thus
rupturing the branch circuit T, at two points, as shown in figure 17, thereby
causing the armature of the polarized relay to leave its contact w, the result being
the liberation of both the inlet and exhaust valves from their respective magnets,
and the consequent application of the brakes.
•
On the other hand, should a break occur on the other side of said relays, as
at N', in figure 16, the relay R¹, only, would at first, be demagnetized and release
its armature so as to break the circuit T, the demagnetization of the relay R, not
taking place till after the circuit T, was so broken, because its armature being
down against its contact s², would remain down though the circuit were broken
at N1, by reason of the uninterrupted flow of the current through the circuit T.
The necessity therefore of employing two relays when the generator or the
engine carrying the generator is desired to be connected to either end of the train
is made apparent.
Where the engine is always connected to the same end of the train, it is only
necessary to employ one relay and that, a polarized one, as shown in figure 19,
with this arrangement the direct current will shift the polarized armature and
cause the current to pass through both circuits T and V, and effecting the closing
of the inlet valve, and the opening of the exhaust valve, while a breaking of the

page_text: circuit between the relay and generator will cause both magnets to release their
armatures opening the inlet and closing the exhaust valve and applying the brakes,
and the re-establishment of the circuit, with a reverse current, will cause the
circuit V, to remain open but will pass the current through the circuit T, in a
inanner to close the inlet valve and retain the pressure in the brake cylinder, the
exhaust remaining in the meanwhile closed.
Still another embodiment of my invention is to be found in figures 23 and 24,
of which,―
Figure 23, is a diagram showing the application of my invention to a train of
two cars.
Figure 24, represents a modification of the arrangement shown in figure 23.
A, represents a valve casing containing a tubular inlet valve F, and a tubular
exhaust valve G.
The upper end of the inlet valve F, operates within a small chamber e, which is in
communication through a pipe f, in the auxiliary compressed air reservoir and the
upper end of the exhaust valve G, operates within another small chamber e¹,
which is in communication with the atmosphere, while the lower ends of both said
valves operate within small chambers e2, e2, in communication with each other and
with the brake cylinders through a pipe h.
The inlet valve F, seats upward while the exhaust valve G, seats downward and
each is provided with suitable packings i, to prevent leakage of air.
The inlet valve F, is controlled by an electro magnet, H, and the exhaust
valve G, is controlled by an independent electro magnet, I, the said two electro
magnets being arranged in a local circuit, K, charged either by a primary or a
secondary battery or batteries or in any other suitable manner.
Each car is provided with an equipment such as just described.
A main electric circuit L, L', extends throughout the train.
This main circuit has interposed in it, on each car an ordinary relay or electro
magnet M, having a neutral armature N, which is adapted to form part of that
portion of the local circuit in which the electro magnet H, controlling the inlet
valve is included, and it has also interposed in it, on each car, a polarized relay O,
whose polarized armature P, is adapted to form part of that part of the local
circuit which includes the electro magnet I, which controls the exhaust valve G.
Upon the engine is mounted a suitable current generator for charging the main
circuit and which is preferably an ordinary battery.
-
The wires from the generator extend to a suitable current reverser such for
instance as shown in figure 23, wherein one of said wires, designated as is
connected to a contact finger 1, and the other wire, designated + is connected to
a contact finger 2, while the outgoing circuit wire is connected to a contact
finger 3, and the return wire to a contact finger 4.
The ends of all these contact fingers are adapted to bear upon a cylinder R,
the body of which is of insulating material but which has metallic conducting
portions 5, 5, 6, and 7, upon it.
When the cylinder is turned so as to bring the fingers 2, 3, upon one metal
surface 5, and the fingers 1, and 4, upon the other metal surface 5, a direct current
will be sent through the circuit, which will cause the armnatures of both the
relay M, and the polarized relay O, to engage with their respective contacts m
and o, and thus close the local circuit through both the valve magnets and cause
the inlet valve to be closed and the exhaust valve to be opened, thereby releasing
the brakes, but when the cylinder is turned so as to bring all the contact fingers
to bear upon its insulated surface the main circuit will be broken and the armatures
of both the relays will be released thus cutting out both valve magnets and
allowing both valves to drop, the inlet valve to open and the exhaust valve to close
and the brakes to be applied.
While the valves are in this position, that is to say, the inlet valve open and the
exhaust valve closed and the brakes on, and it is desired to cut off and hold the
pressure in the brake cylinders, the current reverser is so turned as to cause

page_text: the contact fingers to be brought upon the metal portions 6 and 7, which will
throw a reversed current on the circuit, thereby cutting in the magnet of the inlet
valve and closing the said valve and cutting out the magnet of the exhaust valve
and keeping said last mentioned valve closed.
With the switch or current reverser under his control the engineer is enabled to
apply or release the brakes or keep them under partial pressure at will.
The equipment of each car is the same and consequently the manipulation of the
main circuit affects the brake mechanism of each car alike.
The conductors forming the main circuit may consist of insulated wires laid in
the main air pipes through which the air is supplied or partly of wires so arranged
and partly of the body of the pipe or the rails in the usual manner.
Whenever the main circuit is broken from any cause the brakes will be applied.
Upon each car a circuit breaker such as shown at U, is arranged so as to
enable the conductor to apply the brakes from any car at will.
In the modification shown in figure 24, the valve magnets are arranged in a
local circuit with a switching device which is operated by an electro magnet in the'
main circuit in a manner to cause either or both of the valves to be cut in or out
of the local circuit.
The said switching device consists of a drum A2, adapted to be given a step by
step motion in one direction by means of an anchor-novement B2, actuated by an
electro magnet C³, in the main circuit.
This drum is of metal but has insulation upon it as shown by the dark cross-
lined portions in the drawings.
Cooperating with this drum are a series of fingers D³, E², F².
The finger D², bears at all times upon a metallic portion of the drum, while E²,.F³,
bear respectively upon a metallic portion and an insulated portion or both upon
insulation or both upon metallic portions, according to the position of the drum.
By making and breaking the main circuit by a circuit breaker such as G², for
instance, the drum is advanced step by step.
When both contacts E³ and F2, are on metal portions of the drum, the inlet
valves are closed and the exhaust valves opened, which releases the brakes and
when they are both upon insulation, no current passes in the local circuit, the inlet
valve is open and the exhaust valve closed, thus putting on brakes.
When the contact E², passes from the insulation to metal and the contact F³, at
the same time continues upon metal, the inlet valve will be closed without disturbing
the exhaust valve, which remains closed and the pressure in the brake cylinders
will be retained thus keeping the brakes partially on.
While I have herein shown and described my invention as applied to a brake
system in which compressed air is used for applying the brakes it is evident that
it is equally applicable to the various known vacuum brake systems.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. In an air brake system, a pair of valves arranged in the lines of communi-
cation from a power chamber to a brake cylinder, and from the latter to the
external air, in combination with electro magnets in separate circuits or branches
with the apparatus for making. and breaking such separate circuits or branches so
as to shift such valves either simultaneously or independently, whereby either of
Baid valves may be held open or closed or both held closed or both open: substan-
tially as described.
2. In an air brake system, the combination with the air supply or power
chamber and the brake cylinder, of independent valves for controlling the admission
of air to the brake cylinder and the exhaustion of air from said cylinder, and
electrical apparatus for independently operating said valves whereby the brakes
are enabled to be applied with any desired degree of force and the pressure upon.

page_text: them is enabled to be augmented or diminished without producing a rise and fall
of pressure in the main air pipe and auxiliary reservoir.
3. In an air brake system, the combination with a main air pipe and a series of
brake cylinders arranged on different cars, having pistons connected with the
brakes thereof respectively, of a series of valves arranged to connect said cylinders
through suitable connections with the main air pipe and another series of valves
arranged to connect said cylinders with the external air, of two series of electro
magnets each arranged to operate one series of valves; substantially as described,
whereby independent control is given of each series of valves throughout the train,
and the simultaneous operation of all the valves of either series insured.
4. The combination with the main air pipe of an air brake system, and a series
of auxiliary reservoirs and brake cylinders arranged on different cars, of a series of
valves arranged to connect said cylinders with the auxiliary reservoirs and another
series of valves arranged to connect said cylinders with the external air and two
series of electro magnets each arranged to operate one series of valves independently
of the other series of valves; substantially as described.
5. In an air brake system, the combination with an air supply or power chamber
and a brake cylinder, of an intermediate valve chamber interposed between the
air supply or power chamber and the brake cylinder and having passages leading
from the power chamber to the brake cylinder and from the latter to the external
air and containing two independent valves for controlling said passages and electro
magnets one for each valve, arranged in separate circuits or in different branches of
the same circuit substantially as described.
6. The combination with the valve casings having the independent upper
chambers in communication with the compressed air supply and the external air
respectively, and having the lower chamber in communication with the brake
cylinder, of the tubular inlet and exhaust valves having their ends opening into the
upper and lower chambers as described, the armatures for cooperating with said
valves and the electro magnets by which said armatures are controlled, substantially
as described.
7. In an air brake system the combination with a main air pipe, a series of
brake cylinders arranged one on each car & connected mediately or immediately
to the main air pipe of a series of valves arranged to put the brake cylinders in
connection with the air supply, & another series of independent valves arranged to
connect said cylinders with the external air, two series of electro magnets each
arranged to control one series of valves, & circuit conductors extending throughout
the train and adapted, when separated or broken to operate the electro magnets in
manner to apply the brake, substantially as described.
8. In an air brake system, the combination of a main air pipe extending
throughout the train, the brake cylinders on the several cars connections between
said cylinders and the main air pipe, valves for controlling the inlet and exhaust of
air to and from the cylinders, electro magnets for controlling said valves, an electric
valve circuit extending throughout the train, and one or more pistons with circuit
breaking devices connected thereto controlled by the pressure in the main air pipe,
and adapted, when such pressure falls below a predetermined point to break the
electric valve circuit and cause the brakes to be applied, substantially as described.
9. In the herein described air brake system, and in combination with the main
air pipe and the electric valve circuit of a piston and valve located in the main
pipe and a circuit breaker connected to and operated by the piston to open the
electric valve circuit when the pressure in the air pipe is below a predetermined
point and to open said circuit and at the same time hold back the pressure in the
main air reservoir, when a break or opening of the main air pipe occurs, substan-
tially as described.
10. The combination with the main air pipe of the valve casing interposed
therein having the upper and lower compartments, the valve stem carrying the
piston at its upper end, and the valve and circuit breaking device at its lower end,
and communicating ports leading from the lower compartment and from the upper.

page_text: and lower portions of the upper compartment and the three way cock, substantially
as described.
11. In an air brake system, the combination with a valve arranged in the line of
communication from the power chamber to a brake cylinder, and another indepen-
dent valve arranged in the line of communication from the brake cylinder to the
external air, of a main electric circuit having magnets for separately controlling
the said independent valves and a switching device, operated by a reversal of the
current, to cut out the electro magnet which controls the valve in the line of
communication form the brake cylinder to the external air, substantially as
described.
12. In an air brake system for railway trains the combination, on each car, of
an air supply or power chamber, a brake cylinder and brakes operated thereby, and
separate inlet and exhaust valves for controlling the admission of pressure to the
brake cylinders and the exhaustion of pressure therefrom, with an electric circuit
extending throughout the train and having arranged therein a series of electro
magnets for controlling the inlet valves, and another series of electro magnets for
controlling the exhaust valves, and a switching device operated by reversal of the
current to cut out the electro magnets which control the exhaust valves substan-
tially as described.
13. In an air brake system for railway trains, the combination, on each car, of
an air supply or power chamber, a brake cylinder, brakes operated thereby, and
separate inlet and exhaust valves for controlling the admission of pressure to the
brake cylinder and the exhaustion of pressure therefrom, with an electric circuit
having arranged therein an electro-magnet for controlling the inlet valve, another
independent electro magnet for controlling the exhaust valve, a switching device
operated by the reversal of the current to cut out the electro magnet which
controls the exhaust valve and relays for cutting out or putting in both valve
magnets when the main circuit is broken or established, substantially as described.
14. In an air brake system for railway trains, the combination on each car of an
air supply or power chamber a brake cylinder and brakes operated thereby and
separate inlet and exhaust valves for controlling the admission of pressure to the
brake cylinders and the exhaustion therefrom, with an electric circuit extending
throughout the train and having arranged therein a series of electro magnets for
controlling the inlet valves and another series of electro magnets for controlling
the exhaust valves, a switching device operated by reversal of the current to cut
out the electro magnets which control the exhaust valves and a switch under the
control of the engineer for establishing breaking or reversing the current, in the
main circuit, substantially as described for the purpose specified.
15. In an air brake system, the combination substantially as herein described of
the main air pipe auxiliary reservoir, brake cylinder, intermediate valve casing,
independent inlet and exhaust valve, the inain electric circuit and branch circuits T
and V, the former including the electro-magnet which operates the inlet valve, the
polarized relay and the armatures of the relays or magnets in the main circuit
and the latter including the magnet which controls the exhaust valve and the
arinature of the polarized magnet, the whole constructed and arranged substan-
tially as described.
16. In an air brake system, the combination of the valves which control the air
pressure in the brake cylinders and a local circuit on each car containing an electro
magnet or magnets for operating said valves, with a main circuit extending
throughout the train and containing electro magnetic switching devices for
manipulating all the local circuits so as to cause the simultaneous application or
release of all the brakes, substantially as described.
17. In an air brake system for railway trains the combination with separate
inlet and exhaust valves for controlling the admission of pressure to the brake
cylinder and the exhaustion of pressure therefrom, of a local circuit on each car
ncluding an electro magnet for controlling the inlet valve and an independent

page_text: electro magnet for controlling the exhaust valve, a main circuit extending through-
out the train and switch devices operated by the manipulation of the current in
the main circuit for cutting in or out either or both of the valve magnets,
substantially as described.
18. In an air brake system such as described, the combination with the inlet
valves for controlling the admission of compressed air from the air supply or power
chamber to the brake cylinders and with independent exhaust valves for controlling
the exhaustion of air from the brake cylinders into the atmosphere of separate
electro magnets for operating said inlet and exhaust valves, switching devices for
cutting out or putting in said valve magnets or either of them from or into local
circuits, a main circuit extending throughout the train électro magnets in said
main circuit for actuating the switching devices and means for opening and closing
the main circuit, substantially as described.
19. In an air brake system substantially such as described, the combination with
the separate inlet and exhaust valves, of the local circuits including in separate
branches electro magnets for controlling the said inlet and exhaust valves the main
circuit extending through the train and containing the relays for controlling the
inlet valve magnets and the polarized relays for controlling the exhaust valve
magnets and switching devices for making or breaking or reversing the current on
the main circuit, as set forth.