Improvements in Air Brakes for Railway and like Vehicles.
Year: 1898

page_text: Date of Application, 29th Mar., 1898-Accepted, 18th June, 1898
COMPLETE SPECIFICATION.
Improvements in Air Brakes for Railway and like Vehicles.
I, JOHN JACOB NEF, of 66, West 88th Street, in the City, County, and State of
New York, United States of America, Mechanical 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,
and accompanying drawings, that is to say:-
-
This invention relates to air-brakes in which the pressure of air is supplied by
a pump actuated from the axle of the car and where the pump actuating mechanism
is disconnected from the pump or its connections, when the pump is to be stopped
and is again connected when the pump is to be operated and has for one of its
objects the provision of efficient and reliable means for automatically relieving
the pump from its work of compressing air while the pump is being connected
with its pump operating mechanism, thus rendering it certain that the connection
is completely made before the work of compressing air is begun. A large amount
of wear upon the connecting parts is thus avoided which otherwise will occur
when the pump commences to operate and force air into the reservoir against a
high pressure in the reservoir before the connecting parts are firmly set against
each other.
Another object of this invention is the provision of means whereby the operative
mechanism of the pump is connected as a result of the release of the brakes, and
is automatically disconnected when the air in the reservoir is again raised to its
normal pressure, thus the operation of the pump is begun in a gradual manner
after the car has been stopped and is again started, or after its speed has been
slackened, and is automatically stopped when the pressure in the reservoir is
restored.
Another object of this invention is the provision of efficient and reliable means
for automatically connecting the operative mechanism of the pump when the fluid
pressure falls below a certain degree.
It also consists in the novel construction, combination and arrangement of
parts hereinafter described.
In the drawings accompanying and forming a part of this specification,
Fig. 1 is a general view showing the pump with its actuating mechanism, a
pump governor, a reservoir in which compressed fluid is stored, a service valve
and a brake cylinder.
Fig. 2 is a sectional view of the service valve.
Fig. 3 is a detail of the ports formed in the bottom portion of the service
valve.
Fig. is a cross-section of Fig. 2 through plane of line 4-4.
Fig. 5 is a sectional view of the pump governor on line 6-6 Fig. 7 and 9-9
Fig. 6.
Fig. 6 is a detail of the valve in said pump governor and the relative positions
of ports governed by it, and
Fig. 7 shows in part a cross section of the pump governor through plane of
line 77 and a sectional view of the pump and two of its valves on line 8-8

page_text: Similar characters of reference designate like parts in all figures.
This mechanism comprises in a general way the reservoir A, the service-valve B,
the governor C, the pump and pump operating mechanism I) and the brake-
cylinder E.
In the preferred form of my invention herein shown and described the service-
valve B comprises a valve chamber 6 formed of a valve casing c and base plate d, a
piston e, a piston rod f, a valve 7, port h leading to the brake cylinder E, port i
leading to the governor C and a connection F with the reservoir A.
Governor C comprises a valve chamber j, formed of a valve casing k, with
head, having within it a piston m, hollow piston rod n, spring o and valve p, a
compound cylinder G, having head g, pistons r and s, rod t. connecting said pistons
and port u admitting air from valve chamber j to larger cylinder v, and exhaust
port and passage way from smaller cylinder y, and also an auxiliary
chamber z formed of a casing zz communicating through passage way jj with
chamber and exhausting through port a and pipe H to chamber I of pump D
on the lower side of piston J.
Pump D is of any approved form, and is supplied with inlet valves K K
Figures 7 and 1. Underneath valve K is a piston J and underneath said piston
is chamber I connected by pipe H with the exhaust port a.
Spring ss tends to maintain piston J in its lower position. Pump D supplies
air to the reservoir through connection L and is thrown into and out of operative
connection by engagement of a suitable clutch as M. The brake-cylinder Eis
of any approved form, is provided with the usual piston and connections and has
a pipe connection N with port h of service valve.
The pump is thrown in and out of engagement with its operating mechanism
by the movement of lever P pivoted at one of its ends to standard Q and connected
to piston rod t. Said lever forms a collar encircling clutch member R of clutch M
between shoulders provided thereon for the retention of said collar. As said
piston rod is reciprocated said lever is swung on its pivot to force clutch
member R in and out of engagement with the other clutch member M. As
shown in the drawings, the said piston rod and pistons are in the position for the
disengagement of the pump operating mechanism.
The smaller cylinder y is in open communication at all times with the reser-
voir A and consequently the reservoir pressure is acting at all times on the smaller
piston r. The larger cylinder has communication with the valve chamber j
through port u which port is opened and closed by valve p; the valve also
controls the exhaust from cylinder through port u and the exhaust port w, and
also controls the admission of air from valve chamber to auxiliary chamber z
through passage way, and also the exhaust from auxiliary chamber z through
port and pipe H. Owing to the difference in the sizes of the pistons r and s
it is clear that when pressure is admitted to cylinder the pistons will be moved
to the left and the pump operating mechanism thrown out of engagement; it
is likewise clear that when air is exhausted from cylinder the pump operating
mechanism will be thrown into engagement for the reason that the reservoir
pressure acts at all times on piston r.
The valve p is attached to the hollow piston rod n to which is attached also the
piston m; the spring o in the hollow piston rod tends to force said piston rod to
the right as shown in Fig. 5 and to move valve to shut off from cylinder v the
pressure in valve chamber which through passageway r has within it at all
times reservoir pressure from cylinder v, and to open said cylinder to the
exhaust. The pressure in valve chamber acting upon piston m tends to move
said piston rod and valve to the left, that is to open communication between the
valve chamber. j and cylinder v, from which it follows that when the pressure
in valve chamber j falls below a point sufficient to counter-balance pressure of
spring o, said spring will cause valve p to exhaust the air from cylinder v, thereby
permitting the pressure on piston r to throw the pump mechanism into engage
ment, and when the pressure in valve chamber rises above said point it will

page_text: tend to overcome the spring and as such pressure is increased it will move
valve to the left and admit pressure to cylinder and throw the operating
mechanism of the pump out of engagement. It will be noted that the pump will
not be thrown out of engagement until valve has practically completed its
travel to the right for until then the lap of the valve will not open cylinder v
to the exhaust; it will be further noted that having been thrown into engage-
ment the pump will not be thrown out of such engagement until the valve has
practically completed its travel to the left for until then its lap will not uncover
port u to open communication between cylinder and valve chamber j.
The movement of valve p to the right to exhaust the air from cylinder and
to cause the pump operating mechanism to be thrown into engagement as has
been described is also accomplished when the brakes are released and the air from the
brake cylinder exhausted through the pipes N and ii into the space mm to the left of
piston m, the air from the brake cylinder finally escaping through the opening l
after the piston has completed its movement. This occurs when the brakes
having been previously applied by a movement of the valve g in the service
valve B to the right are released by a movement of said valve in the opposite
direction opening communication between pipes N and ii. Through the applica-
tion of the brakes the pressure in valve chamber j falls slightly, and valve p
moves toward the right but not sufficiently to exhaust the air from cylinder v;
when the brakes are released the air from the brake cylinder forces it to its
extreme right, the air from cylinder vis exhausted and the pump thrown into
operation. When the exhaust from the brake cylinder escapes through open-
ing 17 valve p will immediately return to the position it occupied just before the
brakes were released, but until its return to practically its extreme left position
(which it will not do until the pump has operated to restore to the reservoir the
pressure lost in the application of the brakes) the pump will remain in operation
as has already been explained.
The brakes are applied by a movement of piston rod f on which is mounted
piston e toward the left against the pressure of air in the valve chamber B which
is always in open communication with the reservoir through pipe connection F.
Piston rod is moved toward the left by the operator through lever or other
connections with the platform of the car. This movement of the piston rod
carries with it the valve g connected to piston rod f and uncovers port h leading
to brake cylinder E, thus admitting air at reservoir pressure to said brake
cylinder. When the operating lever is released the reservoir pressure in said
valve chamber acting against said piston at the left will force said piston to its
extreme right position returning valve to its original position exhausting the
air from said brake cylinder through pipes N and ii as has already been explained.
Porth is provided with a narrow extension hh Fig. 3, for the purpose of
admitting a small amount of air to the brake cylinder by a partial movement of
valve g, a further movement of valve g will allow a greater volume of air to pass
to brake cylinder through port h.
To overcome the shock and wear upon the pump and pump operating mechanism
when they are thrown into engagement while the car is moving, I provide means
for automatically relieving the pump of its work of compressing air until the
engagement of its operating parts has been fully effected. For accomplishing
this I provide an auxiliary chamber heretofore partially described.
Chamber z has communication with valve chamber through passage way jj,
said passageway being controlled by valve pin valve chamber in such a way
that when rod n is moved to the right to throw the pump into action the
passageway jj is closed from valve chamber j and opened to pipe H thereby
exhausting air through pipe H under piston J thereby lifting the valve K from
its seat and opening communication between the compression chamber of the
5 pump and the atmosphere; said valve being held open until the air in auxiliary
chamber has exhausted around the piston to the atmosphere through port KK.
While this valve K is thus held open, the 'air is free to pass from the compression

page_text: chamber of the pump into the atmosphere and consequently no compression takes
place and the pump and its operating mechanism are relieved from all strain
which occurs when the pump is pumping against reservoir pressure. When the
air below the piston J has exhausted the spring ss lowers piston J and permits
valve K to return to its seat and compression in the pump begins.
When the pressure in the reservoir is restored and its action on piston m moves
valve P to the left causing a disengagement of the pumping mechanism as here-
tofore described, the movement of the valve also closes auxiliary chamber z from
the exhaust and opens it to valve chamber admitting air therefrom to said
auxiliary chamber ; valve p is so arranged with respect to ports u and jj that
when it is moved to the right port jj is opened to pipe H before port u is opened
to the exhaust. Said valve has recesses ww and a a Fig. 6 one forming an
air passage
from cylinder v to exhaust port w through port u and the other form-
ing an air passage from auxiliary chamber z through port jj to pipe H. By this
arrangement air is exhausted from auxiliary chamber through pipe H to open
valve K prior to the exhaust from chamber through port w which allows the
movement of piston rod t to the right to throw the clutch members R and M
into engagement, thus making it certain that valve K is open before the clutch
members are thrown into engagement.
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 the combination with an air reservoir, a pump and
pump operating mechanism, a pump governor and brake cylinder of a service
valve through which the brake cylinder is controlled, and means for throwing
the pump into operation by the exhaust from the brake cylinder when the brakes
are released, substantially as described.
2. In an air brake system the combination with an air reservoir, a pump and
pump operating mechanism, a pump governor and brake cylinder of a service
valve through which the brake cylinder is controlled, means for throwing the
pump into operation by the exhaust from the brake cylinder when the brakes are
released, and means for automatically throwing the pump out of operation by
the pressure of air in the reservoir, substantially as described.
3. In an air brake system the combination with an air reservoir, a pump and
pump operating mechanism, a pump governor and brake cylinder of a service
valve, means whereby upon the movement of the service valve in one direction
air may be admitted to the brake cylinder and means whereby upon the move-
ment of the service valve in the opposite direction the air may be exhausted
from said brake-cylinder to the governor and cause the same to throw the pump
into operation, substantially as described.
4. In an air brake system the combination with an air reservoir, a pump and
pump operating mechanism, a pump governor and brake cylinder of a service
valve communicating with said air reservoir, a port leading from said service
valve to the brake cylinder, an exhaust port leading from said service valve to
the pump governor through which air may be exhausted from said brake cylinder
to said pump governor and cause the same to throw the pump into operation,
substantially as described.
5. In an air brake system the combination with an air reservoir, a brake
cylinder, a pump and pump operating mechanism, an automatic governor having
a valve, said valve being impelled in one direction by air under pressure cylinder
to exhaust to the atmosphere, substantially as described.
7. In an air brake system the combination with an air reservoir, a pump and
pump operating mechanism, a brake cylinder and service valve controlling said
brake cylinder of an automatic pump governor having a piston adapted to throw
the pump into and out of operation and connections with said brake cylinder
through which air is exhausted from said brake cylinder to actuate said piston

page_text: to throw the pump into operation, and mechanism for automatically actuating
said piston to throw the pump out of action when the pressure in the reservoir has
reached a predetermined point, substantially as described.
8. The combination in an air brake system of a pump and pump operating
mechanism of a compound air cylinder comprising two cylinders of different
diameters, a piston within said compound cylinder having heads of different
diameters corresponding with the bores of said compound cylinder, a valve
chamber in open communication with the smaller cylinder and having a port
communicating with the larger cylinder and an exhaust port, a valve in said
valve chamber, and means acting under variations in air pressure for operating
said valve to alternately open and close said larger cylinder to the valve chamber
and the exhaust, substantially as described.
valve
9. The combination in an air brake system of a pump and pump operating
mechanism, of a compound air cylinder comprising two cylinders of different
diameters, a piston within said compound cylinder having heads of different
diameters corresponding with the bores of said compound cylinder, a
chamber having open communication with the smaller of said cylinders, and
having a port connecting with the larger of said cylinders, an exhaust port, and
a valve controlling said ports whereby air is admitted to the larger cylinder to
move the piston in one direction and exhausted therefrom to move it in the
opposite direction, substantially as described.
10. The combination in an air brake system of a pump and pump operating
mechanism, a compound air cylinder comprising two cylinders of different dia-
meters, a piston within said compound cylinder having heads of different dia-
meters corresponding with the bores of said compound cylinder, a valve chamber
having open communication with the smaller of said cylinders and having a port
connecting with the larger of said cylinders, an exhaust port and means for con-
trolling said ports whereby air is exhausted from the larger cylinder to allow
the piston to move in one direction, and is admitted to said cylinder to move the
piston in the opposite direction, substantially as described.
11. In an air brake system the combination with an air reservoir a pump and
its operating mechanism a pump governor connecting and disconnecting said
pump operating mechanism and the pump of means whereby the compression
chamber of the pump is opened to the atmosphere while said pump operating
mechanism is being connected with said pump, substantially as described.
12. In an air brake system the combination with an air reservoir, a pump and
its operating mechanism, a pump governor connecting and disconnecting said
pump operating mechanism and said pump of means whereby the suction valve
of said pump may be controlled by the operation of said pump governor sub-
stantially as described.
13. In an air brake system the combination with an air reservoir, à pump and
its operating mechanism a pump governor connecting and disconnecting said
pump operating mechanism and the pump of an auxiliary chamber and means
whereby when the pump is stopped said auxiliary chamber is supplied with air
5 under pressure, and the pump is started said air supply is shut off and the air
in said auxiliary chamber is caused to actuate a valve on the pump to open
communication between the compression chamber of the pump and the atmo-
sphere.
14. In an air brake system the combination with an air reservoir, a pump and
0 its operating mechanism, a pump governor connecting and disconnecting said
pump operating mechanism and said pump of an auxiliary air chamber having
communication with the valve chamber of said pump governor under the control
of the valve therein, mechanism whereby the suction valve of said pump may be
controlled and a communication between said auxiliary air chamber and said
5 suction valve controlling mechanism, substantially as described.
15. In an air brake system the combination with an air reservoir, a pump and
its operating mechanism, a pump governor connecting and disconnecting said

page_text: pump operating mechanism and the pump of an auxiliary chamber, a communi-
cation from said auxiliary chamber to a port in the valve chamber of the pump
governor, said communication being operated by the movement of the valve in
the valve chamber which throws the pump out of action and closed by the reverse
movement, a communication between the auxiliary chamber and the suction valve
of the pump, whereby when the valve in the valve chamber is moved to start the
pump communication is opened between the auxiliary chamber and the said
suction valve of the pump causing said suction valve to open and whereby a
movement of the valve in- the, valve chamber of the pump. governor in the
opposite direction closes said port in said auxiliary chamber..
16. The combination in a service valve with a valve chamber and a valve for
controlling the passage of compressed air, of a piston connected with said valve
and adapted to reciprocate in a cylinder in communication with said valve
chamber, said piston being normally under air pressure exerted in one direction
and means for mechanically moving the piston and valve in the opposite direction,
substantially as described.
17. The combination in a service valve with a valve chamber and a valve, of
means for operating the said valve in one direction by the air pressure within
the valve chamber and in the other direction by external mechanical means
against the pressure of the air, substantially as described.
Date : 201
N1 1000
EDWARDS AND Co.,
65 and 66, Chancery Lane, London, Agents for the Applicant.