Improvements in and relating to Automatic Brakes for Railway Trains.
Year: 1890

page_text: Date of Application, 12th July, 1890-Accepted, 4th Oct., 1890
COMPLETE SPECIFICATION.
Improvements in and relating to Automatic Brakes for
Railway Trains.
I, ALBERT PARSONS MASSEY, of the City of Watertown, in the County of Jefferson,
in the State of New York, one of the United States of America, Engineer, 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 my invention relates to automatic brakes for railway trains wherein compressed
air is used as the motive power.
In order that the said invention may be fully understood I now proceed particularly
to describe the same, and for that purpose refer to the several figures on the annexed
sheets of drawings, the same numerals of reference indicating corresponding parts in
all the figures.
Figure 1 is a sectional view of the air compressor.
Figure 2 is a top view of the same.
Figure 3 is a sectional view of the engineer's valve.
Figure 4 is a side view of the same.
Figure 5 is a top view of the same.
Figure 6 is a top view of the automatic valve attached to a portion of a brake
cylinder partly in section
off."
Figure 7 is a sectional view of same with the valve in position for "brakes off."
Figure 8 is a sectional view of the valve in position for "brakes on full."
Figure 9 shows the ports in the valve and valve seat when the brakes are
Figure 10 shows the ports in the valve and valve seat when the brakes are partially
applied.
full on."
Figure 11 shows the ports as above when the brakes are
Figure 12 shows a sectional view of a modified form of the valve with a flat valve
in place of a cylindrical valve.
In Figures 1 and 2 of the drawings, the numerals 1 and 2 indicate steam cylinders,
in the drawings 1 and 2 are steam cylinders, 3 and 4 are air cylinders, 5 and 6 are
valves for controlling the action of the steam pistons, 7 and 8 are valve stems, 9 and
10 are valves admitting air alternately to the larger air cylinder, 11 and 12 are valves
between the two air cylinders, 13 and 14 are valves between the smaller air cylinder
and the reservoir connected to pump at 15. Steam is admitted to the steam chests 16
and 17 through port 18, and is exhausted through port 19. The valve stems 7 and 8
are actuated by the plates 20, which are secured to the pistons and come in contact
with the tappets on the valve stem. The cycle of operations is as follows::
In the position shown, the air piston in cylinder 4 has completed its downward
stroke and compressed its contents through valve 12 into cylinder 3; and plate 20 on
steam piston 21 has moved valve 6 to its lowest position: this admits steam through
port 23 to upper side of piston 22 and will cause the piston to descend and expel the
partially compressed air in cylinder 3 through valve 14 and passage 15 into the
reservoir. Meanwhile the cvlinder 4 has become filled above the piston with air at
atmospheric pressure through valve 9, and the cylinder 3 will be filled with air at
atmospheric pressure through valves 9 and 11, both of which open inward and are
seated by gravity. When piston 22 reaches the end of its downward stroke, the
plate 20 strikes the tappet on valve stem 7, and moves valve 5 to its lowest position.
thus uncovering port 24 and admitting steam through ports 24-25-26 to the lower
side of piston 21 thus causing piston 21 to rise and compress the air which is in
cylinder 4, through valve 11 into upper part of cylinder 3. Just as piston 21
completes its stroke, its plate 20 strikes the tappet on valve stem 8 and moves valves 6
brakes off."
off."
Figure 7 is a sectional view of same with the valve in position for "
Figure 8 is a sectional view of the valve in position for "brakes on full."
Figure 9 shows the ports in the valve and valve seat when the brakes are
Figure 10 shows the ports in the valve and valve seat when the brakes are partially
applied.
"
full on."
Figure 11 shows the ports as above when the brakes are
Figure 12 shows a sectional view of a modified form of the valve with a flat valve
in place of a cylindrical valve.
In Figures 1 and 2 of the drawings, the numerals 1 and 2 indicate steam cylinders,
in the drawings 1 and 2 are steam cylinders, 3 and 4 are air cylinders, 5 and 6 are
valves for controlling the action of the steam pistons, 7 and 8 are valve stems, 9 and
10 are valves admitting air alternately to the larger air cylinder, 11 and 12 are valves
between the two air cylinders, 13 and 14 are valves between the smaller air cylinder
and the reservoir connected to pump at 15. Steam is admitted to the steam chests 16
and 17 through port 18, and is exhausted through port 19. The valve stems 7 and 8
are actuated by the plates 20, which are secured to the pistons and come in contact
with the tappets on the valve stem. The cycle of operations is as follows::
In the position shown, the air piston in cylinder 4 has completed its downward
stroke and compressed its contents through valve 12 into cylinder 3; and plate 20 on
steam piston 21 has moved valve 6 to its lowest position; this admits steam through
port 23 to upper side of piston 22 and will cause the piston to descend and expel the
partially compressed air in cylinder 3 through valve 14 and passage 15 into the
reservoir. Meanwhile the cvlinder 4 has become filled above the piston with air at
atmospheric pressure through valve 9, and the cylinder 3 will be filled with air at
atmospheric pressure through valves 9 and 11, both of which open inward and are
seated by gravity. When piston 22 reaches the end of its downward stroke, the
plate 20 strikes the tappet on valve stem 7, and moves valve 5 to its lowest position.
thus uncovering port 24 and admitting steam through ports 24-25-26 to the lower
side of piston 21 thus causing piston 21 to rise and compress the air which is in
cylinder 4, through valve 11 into upper part of cylinder 3. Just as piston 21
completes its stroke, its plate 20 strikes the tappet on valve stem 8 and moves valves 6

page_text: to its highest position, uncovering port 27 and admitting steam through 27, 28, 29 to
the lower side of piston 22, causing the piston to rise and expel the partially compressed
air in cylinder 3 through valve 13 into passage 15 and thence into the reservoir.
While the pistons were compressing the air above them into the reservoir, the air
cylinder below the pistons would fill with air at atmospheric pressure through valves 10
and 12 ready for another cycle of operation.
In a single cylinder air pump the resistance in the air cylinder varies each stroke
from 0 to the extreme pressure in the reservoir, say 100 lbs. The steam piston must
therefore have sufficient area to produce this final pressure and expel the air into the
reservoir in other words, the steam piston must be as large as the air piston in
ordinary locomotive practice where the usual pressure in the boiler is from 120 lbs.
upwards.
In my invention the extreme resistance to the leading piston (21) is to compress
the contents of the two air cylinders into one; the area of the leading air cylinder (4)
can therefore be as much greater than the steam cylinder. as the steam pressure
exceeds the final pressure in the air cylinder with due allowance for friction etc.
In practice the area of cylinder may be twice that of cylinder 2, the other cylinders 1
and 3 are the same size as 2; it follows therefore that the final resistance in cylinder 4
would be the pressure resulting from compressing three volumes of air into one volume
or 45 lbs. above atmospheric pressure. A steam cylinder of one half the area would
therefore be ample with steam at 120 lbs. When the cylinder 3 is filled with air at
45 lbs. pressure, the resistance each stroke will vary from 45 lbs. to 100 lbs. and a
steam piston of the same area will be required to expel the air into the reservoir.
Thus it may be seen that two cylinders full, or volumes of steam at boiler pressure,
will deliver three volumes of air into the reservoir whereas, in a single cylinder
air pump two volumes of steam at boiler pressure would deliver but two volumes
of air into the reservoir.
In Figures 3, 4 and 5 of the drawings, the numeral 31 is a cylindrical case in
which is fitted a piston 32 and a flexible diaphragm 33. This piston and diaphragm
are both attached by links to a bell-crank lever 34 turning about a fixed fulcrum 35.
The arms of the bell-crank 34, are placed at sucli an angle with each other, that
when it revolves about its fulcrum, towards the piston, the effective leverage of
the diaphragm 33 increases, while the effective leverage of the piston 32 decreases.
36 is a tube which may be connected with a reservoir containing compressed air,
this is open through passage 37 to the interior of the case 38 between the piston
and diaphragm; it is also open to the top of valve 39. The space 40 above the
piston is open to tube 41, and thence to a pipe or reservoir in which an air
pressure is desired different from that in tube 36 and its reservoir. 39 is a valve
between tube 36 and chamber 40; 42 is a valve between chamber 40 and the
atmosphere. 43 is a lever fulcrumed on an eccentric stem 44 of the spindle 45:
one end of lever 43 is connected to the piston 32 by the pin 46, the other end
projects under pin 47 in valve 42; this lever also has a slot that encloses pin 48
on lever 49, through which it actuates lever 49. The spindle 45 passes through
the side of the valve case, and is actuated by the lever and handle 50. When
this invention is placed on a locomotive to actuate air brakes the tube 36 is
connected to the main air reservoir, which is kept supplied with compressed air
by a pump. The tube 41 is connected to the train-pipe. When the train is
running, the air in the train-pipe is kept at, or near the pressure in the main
reservoir.
To apply the brakes moderately, the air pressure is reduced a definite amount
which causes the valves under the cars to act and admit a light air pressure to the
brake cylinders. To apply the brakes with full force, the pressure in the train-
Dipe is still further reduced. To release the brakes the pressure in the train-pipe
is restored to its normal pressure.
The operation of this invention, to accomplish the above action, is as follows:
As shown in the drawing, valve 39 is open, and consequently, there is the same
air pressure in the reservoir and in the train-pipe: the pressure is therefore the

page_text: same on both sides of the piston 32.
When the
As piston 32 is in equilibrium, the air
pressure on the diaphragm 33 forces it downward and turns the bell-crank 34 in
the position shown. If now the spindle 45 is turned a little, moving the eccentric
pin 44 upward and toward the right, it will swing lever 49 away from valve 39
and allow it to close by gravity. It will also raise valve 42 by means of the
pin 47, and allow air to escape from chamber 40 to the atmosphere.
pressure in chamber 40 is reduced below that in chamber 38, the piston 32 is no
longer in equilibrium, but is pressed upward with a force equal to the difference
in the two pressures.
This upward pressure is resisted by the pressure on the
diaphragm 33 in a downward direction, but the effective leverage of the piston 32
on the bell-crank 34 is much greater than that of the diaphragm 33 on the same
bell-crank. The piston therefore starts upward. As the piston moves upward, its
effective leverage on the bell-crank decreases, while that of the diaphragm increases,
and when the effective leverages become equal, inversely to the opposing forces,
the upward movement of the piston will cease; the distance to which the piston
will travel therefore, depends on the difference of pressures on its opposite sides.
When the piston rises, it raises one end of lever 43 and allows valve 42 to close.
If the fulcrum of the lever is raised by the eccentric pin 44 but a little, the
piston 32 will need to raise but little to allow valve 42 to close, and therefore it
will close when the pressure in chamber 40 is reduced a little. If the fulcrum is
raised higher, it will require a greater reduction of pressure in chamber 40 to
raise the piston high enough to allow valve 42 to close, and consequently, a
greater amount of air will escape before the valve closes and the train-pipe
pressure will be reduced a greater amount. When the pressure in chamber 40 is
must less than that in chamber 38, the eccentric pin 44 will stand much higher than
in the drawing, and the piston 32 will have raised enough to allow valve 42 to
close. To restore the pressure in chamber 40, the spindle 45 is moved in the
opposite direction. The lever 49 partakes of all the movements of lever. 43, except
that it approaches valve 39 when lever 43 recedes from valve 42, and it
recedes from valve 39 when lever 43 approaches valve 42. Therefore, when
spindle 45 is turned in the opposite direction, and brings the fulcrum of lever 43
downward and to the left, it causes lever 49, to raise valve 39 and admit air from
tube 36 to the chamber 40. As the pressure above the piston 32 increases, 'it
destroys the balance between the piston and diaphragm, and the piston is there-
fore drawn downward by the excess of pressure on the diaphragm, until the bell-
crank 34 has revolved enough to equalize the leverages again. As the piston
moves down, it causes the lever 49, through lever 43 to recede from valve 39.
If the eccentric pin 44 has been depressed but little, a slight motion of the piston
will allow valve 39 to close, but if 44 has been depressed to its lowest position.
the piston would have to descend to its extreme position before the valve 39 could
close. Therefore, the operator can regulate the difference in pressure between the
iwo chambers at will and can increase or diminish them a definite amount by
simply moving the handle a proper distance, as the valves will close automatically
when the desired variation is accomplished. It is obvious that a piston or a spring
might be substituted for diaphragm 33.
In Figures 6 to 12 of the drawings, the numeral 51 represents the brake.
cylinder of a car, 52 is an intermediate chamber between the brake cylinder and
the auxiliary reservoir, 53 is a chamber connected directly with the auxiliary
reservoir through pipe 54. (Figure 6.) Chamber 53 is a cylinder in which is
fitted a piston 55 near one end, and a flexible diaphragm 56 at the other end.
The portion of this cylinder between the piston and the cap marked 57, is con-
nected by the passage 58 with the orifice 59 which is connected to the train-
pipe, 60 is an oscillating valve which is actuated by valve spindle 61 and is kept
to its seat by the spring 62 in the valve spindle. 63 is a lever having a fulcrum
at 64 and connected by links to piston 55 and diaphragm 56 at such an angle
that the effective leverage of one will increase when the other decreases, for when
the lever rises the effective leverage of the piston 55, to turn"the lever about the

page_text: The
fixed fulcrum 64 grows shorter and the effective leverage of the diaphragm 56
grows longer but when the lever is depressed the leverage of the piston grows
longer and the leverage of the diaphragm grows shorter 65 is a jaw in lever 63,
which encloses the pin 66 on valve spindle 61 and through it actuates valve 60.
The passage 67 connects the train-pipe 59 with the port 68 in the valve-seat.
The passage 69 connects the brake cylinder with port 70 in the valve-seat.
passage 71 connects intermediate chamber 52 with port 72 in the valve-seat.
The port 73 is open to the atmosphere. In the valve (Figures 9, 10 & 11) 74
and 75 are ports open only on the face of the valve; they are connected by a
cored passage.
76 is a port passing directly, through the valve. In the modifica-
tion shown in Figure 12 a slide valve 79 is substituted for the oscillating valve 60.
This valve and its valve-seat 80 have the same ports as shown in Figures 9, 10, 11
and these ports are connected with the same chambers as above described. The
lever 63 is changed in form to that of 77, but its action is the same.
By means of these improvements the following objects are attained: Assuming that
the apparatus is attached to a train pipe, a brake cylinder and an auxiliary reservoir as
used on cars, and that the train-pipe is supplied with compressed air at a suitable
pressure; then by simply varying the pressure in the train-pipe the brakes may be
applied easily with a definite pressure and carry that pressure without increasing or
decreasing the same; the brakes may be applied slowly, but finally attain full force;
the brakes may be applied quickly for emergency stops; they may be quickly released.
The operation is as follows. Figure 7 shows the valve 60 in its normal position.
Figure 9 is a plan of the valve and seat when in this position. Compressed air
passes from the train-pipe 59, through passage 67 and port 68 to chamber 53, which
is connected with the auxiliary reservoir; from chamber 53 it will also pass through
ports 76 and 72 and passage 71 to the intermediate chamber 52; it will also pass
from 59 through passage 58 to chamber 57 above the piston. The pressures will
therefore be the same in the intermediate chamber 52, the auxiliary reservoir 53 and
the train-pipe chamber 57. The chamber 52 has about one-fourth the capacity of the
brake cylinder. The piston 55, having the same air pressure on both sides, is in
'equilibrium, and the air pressure on diaphragm 56 draws the lever 63 downward
and holds the valve 60 in its normal position. If now the pressure in the train-
pipe is reduced say 5 pounds, the pressure in chamber 57 will be less than in
chamber 53, and there will therefore be an upward pressure on the piston 55 equal
to the difference in the pressure on its respective sides. As the piston 55 is
connected to lever 63 with an effective leverage many times greater than the effective
leverage of diaphragm 56, a very slight upward pressure is sufficient to move
lever 63 and with it spindle 61 and valve 60; but as soon as motion commences,
the effective leverage of piston 55 decreases and that of diaphragm 56 increases
so that a short upward motion is sufficient to bring piston 55 and diaphragm 56
in equilibrium, and thus hold lever 63 and valve 60 in a new position, a certain
distance from the normal position. If the train-pipe pressure is reduced a greater
amount, the greater difference in pressure on opposite sides of piston 55 will draw
up lever 63 a greater distance before the effective leverages of piston 55 and dia-
phragm 56 will be in equilibrium, and therefore the valve 60 will be moved a
greater distance. The proportions of the piston and diaphragm, and the angle
between their leverages on 63, are so adjusted that a slight reduction of pressure in
the train-pipe will move the valve 60 to the position shown in Figure 10. Referring
to Figure 9 port 68 opens train-pipe to auxiliary reservoir. port 70 opens to brake
cylinders, port 73 opens to the atmosphere, and consequently the brake cylinder is
open to the atmosphere through 70-75-74 and 73, port 72 opens to intermediate
chamber 52. When the valve has moved, as in Figure 10, the train-pipe port 68 is
closed, the port 73 is closed and cuts off communication between the brake cylinder
and the atmosphere; the port 76 is closed, cutting off the auxiliary reservoir from the
intermediate chamber, and the port 75 opens port 72 to port 70, thus allowing air to
flow from the intermediate chamber to the brake cylinder. As the intermediate chamber
is about one-fourth the capacity of the brake cylinders, the air in itwill expand to about

page_text: 4. In a fluid pressure valve mechanism. two pistous or diaphragms connected by a
bell-crank lever so that the effective leverage of one increases when the effective
leverage of the other decreases, a cylinder connected with a source of supply of fluid
pressure, enclosing said pistons or diaphragms so that they are exposed to the fluid
pressure on the inner sides, but one is exposed to atmospheric pressure on the outside
and the other is exposed to the train-pipe pressure in a chamber connected with a
train-pipe, a valve opening from the train-pipe chamber to the atmosphere, a lever
connected at one end with said valve, and at the other end with the piston mechanism
and a moveable fulcrum for said lever, combined in such a manner that when the valve
is opened by means of the lever and moveable fulcrum the reduction of pressure in the
train-pipe will allow the piston to raise the other end of the lever and close the valve,
substantially as set forth.
5. In a fluid pressure valve mechanism, a cylinder connected with a source of supply
of fluid pressure, a chamber connected with a train-pipe, a valve controlling an opening
between these two chambers, a lever which actuates said valve, a valve opening
between the train-pipe chamber and the atmosphere and a lever which actuates said
valve and also actuates the lever which actuates the valve between the cylinder and the
train-pipe chamber, combined with a piston situated in the cylinder between the
cylinder reservoir and the train-pipe chamber to actuate said levers and valves, sub-
stantially as set forth.
6. In a valve mechanism for regulating the flow of fluid pressure, the combination
of a cylinder connected with a source of supply of fluid pressure, a chamber connected
with a train-pipe, a diaphragm between the cylinder reservoir and the atmosphere, a
piston between the cylinder reservoir and the train-pipe chamber, a bell-crank lever
connected to said diaphragm and piston by links, a lever with a moveable fulcrum, a
valve between the train-pipe and the atmosphere, a lever moving on a fixed fulcrum
actuated by the lever on the moveable fulcrum, and a valve between the train-pipe
chamber and the cylinder reservoir, substantially as set forth.
7. In a fluid pressure brake mechanism the combination of a train-pipe, auxiliary
reservoir and brake cylinder, with an intermediate chamber and a valve device for
closing the opening from the auxiliary reservoir to the intermediate chamber, and
admitting air from the intermediate chamber to the brake cylinder, and afterwards
closing the intermediate chamber from the brake cylinder and opening the auxiliary
reservoir to the brake cylinder, substantially as set forth.
8. In a fluid pressure brake mechanism the combination of a diaphragm and piston
connected at different angles to a lever in such a manner that the effective leverage of
one will increase when the other decreases, with a valve situated in a chamber connected
with the auxiliary reservoir, whose preliminary traverse admits air from an inter-
mediate chamber to the brake cylinder, and which by a further traverse closes the
intermediate chamber from the brake cylinder and admits air from the auxiliary
reservoir to the brake cylinder, substantially as set forth.
9. In a fluid pressure brake mechanism a governing valve situated in a chamber
connected with the auxiliary reservoir, with ports which will in a preliminary traverse
admit air from an intermediate chamber to the brake cylinder, and by a. further
traverse will close the intermediate chamber from the brake cylinder and open it to the
train-pipe, so that air may flow directly from the train-pipe to the intermediate
chamber, substantially as set forth.
101
1
1800

page_text: one-fifth of the pressure originally in the intermediate chamber, or say 12 lbs. per
square inch. The valve will remain in this position as long as the train-pipe pressure
remains a little below that of the auxiliary reservoir, hence the brakes can be carried,
at the above determined pressure for an indefinite time. If the train-pipe pressure be
increased to that of the auxiliary reservoir, the piston 55 will offer no resistance to the
pressure on diaphragm 56, and the lever 63 will be forced downward bringing the
valve 60 to its normal position, and releasing the brake. For an emergency stop
the pressure in train-pipe is reduced say 20 lbs. this variation on opposite sides of
piston 55, gives such a preponderance of force to piston 55 over diaphragm 56, that it
raises lever 63 high enough to bring valve 60 to the position shown in Figure 11 before
the change in the angle of 63 brings the piston and diaphragm again in equilibrium.
As the valve moves from the position in Figure 9 to that in Figure 11, it opens
ports 70 and 72 to each other as before described, and the excess pressure in inter-
mediate chamber 52, is reduced to 12 or 15 lbs. When the valve reaches position
shown in Figure 11 the brake cylinder port 70 is open to the reservoir pressure which
quickly brings the brake cylinder to full pressure. At the same time ports 72 and 68
are connected by the cored passage from 74 to 75, this allows a portion of the air in the
train-pipe to pass into chamber 52, which has just been partially emptied, and thus
reduces the train-pipe pressure quickly for actuating the valves on the cars farther to
the rear of the train. Restoring the train-pipe pressure to that of the auxiliary
reservoir again brings the valve to its normal position and releases the brakes.
If the train-pipe pressure is reduced 10 or 12 pounds, the valve will be moved to a
position intermediate between Figures 10 and 11, when port 70 will be opened slightly
while port 68 remains closed. In this case the brakes would be applied slowly, but
with full force in three or four seconds.
-
If the train-pipe pressure is reduced 10 or 12 pounds, and then restored to about
5 lbs. below the normal pressure, the valve will move to the intermediate position
described above and then return to position in Figure 10. This will have put the
brakes on to a pressure intermediate between 12 pounds and the full pressure, and will
retain it at that intermediate pressure as long as desired.
It is obvious that by changing the points of attaching the links from the piston and
diaphragm to the lever 63 any varying resistance may be obtained that may be desired.
I have proportioned them in this apparatus to move the valve through its extreme
travel with a variation of 20 pounds pressure in the train-pipe.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. An air compressor with two steam cylinders in which the stroke of one piston is
practically completed before the other one starts, combined with two air cylinders with
valves arranged to admit air at atmospheric pressure to both cylinders, and on the
return stroke to compress the air from the larger cylinder into the smaller cylinder,
and then expel the air from the smaller cylinder into the reservoir, substantially as
set forth.
2. In a duplex air compressor the cylinders 1 and 2 and pistons 22 and 21 each
connected to a piston in an air cylinder, in combination with valve stems 7 and 8
tappets 20 and valves 5 and 6 with ports communicating with each other and with each
end of the opposite cylinder, substantially as set forth.
3. A duplex air compressor consisting of two steam cylinders containing pistons
connected with pistons in two air cylinders; two steam valves arranged in line with
said pistons and actuated by them, a series of ports connecting each steam valve with
both ends of the opposite cylinder, so that the action of each piston controls the move-
ments of the other; two air cylinders, of equal size, with inlet valves from the
atmosphere to the larger cylinder, valves between the larger cylinder and the smaller
cylinder which will also allow the atmosphere to pass intothe smaller cylinder,and valves
between the smaller cylinder and a passage leading to a reservoir, substantially as
set forth.