Improvements in and relating to Air-brakes for Railway Trains.
Year: 1889

page_text: Date of Application, 1st Oct., 1889-Accepted, 2nd Nov., 1889
COMPLETE SPECIFICATION.
Improvements in and relating to Air-brakes for Railway Trains.
I, PETER JENSEN, of 77, Chancery Lane, in the County of London, Fellow of
the Institute of Patent Agents, 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, (a communication to me from abroad
by Harvey Jefferson Ubert, doing business at Number 111, Broadway, in the City,
County and State of New York, one of the United States of America, Merchant)
:-
This invention consists of brake apparatus for railway trains in which straight
air, that is to say, air flowing directly from the main reservoir fills the auxiliary
reservoir and passes through the valve mechanism to operate it, and thence passes
to the brake cylinder to set the brakes; the brakes being released automatically upon
the breaking or parting of the train, or by manipulation of the engineer's valve,
substantially as described and claimed.
The drawing shows in sectional plan one form of apparatus embodying my invention;
and for the sake of conciseness, the description of the invention will be confined to
the form illustrated in said drawing.
A, is the main reservoir connected with any suitable pumping apparatus through
the pipes, a, b, c, in which is interposed a check valve, d, to prevent back-flow of air
from the reservoir. B, is the engineer's valve, the specific construction of which
will be presently described. C, is the auxiliary reservoir.. D, is the triple valve,
so called, and, E, is the brake cylinder.
The main reservoir, auxiliary reservoir and brake-cylinder may be of ordinary
construction; the engineer's valve and the triple valve are of peculiar construction
and form part of the present invention, as will appear in the claims herein made.
Two lines of pipes, F, G, are employed, and each line is connected with each valve
and each auxiliary reservoir of the train and the said lines of pipes extend from the
engineer's valve, B. This valve, B, is composed of a shell, e, in which is arranged a
plug, f, having a port, g, large enough to open communication between the branch
pipe, h, which connects the said valve with the main reservoir, and the two lines
of pipe, F, and, G. The plug is also provided with a port, i, large enough to open
communication between the line of pipe, G, and the exhaust, j, to the atmosphere.
The plug, f, is provided with a handle, k, or other suitable operating device for
rotating it. within the shell, e.
The pipe, F, is connected by a branch-pipe, l, with each of the auxiliary reservoirs,
and in the branch pipe, l, is arranged a check-valve, m, opening against pressure
of incoming air and closing against the outflow of air from the auxiliary reservoir.
The pipe, , is connected to a branch-pipe, n, which extends from the auxiliary
reservoir to the triple valve, d, so that there is an equal area from the main reservoir
to the auxiliary reservoir and to the triple valve for the incoming air.
The line of pipe, G, is connected by branch pipes, o, with the triple valve of each car.
The connections of the pipes, n, and, o, with the triple valve are made upon opposite
sides of the diaphragm, p, which separates the triple valve into two chambers, q,
and, g, of unequal area. In the chamber, 9, is arranged a piston, ", and in
chamber, q, is arranged another piston,, which has an area about one-third greater
than that of piston, ". A stem, is common to the two pistons and works through
a gland or stuffing-box, 73, in the diaphragm or wall, p, which divides the triple valve
into two chambers, as just described. The pistons, ", and, », may be of any suitable
construction; as shown they are composed of two metallic plates between which is
interposed cup-leathers; and washers, 4, and, 6, may be interposed between the
pistons and the diaphragm, p, in order to cushion the stroke of the said pistons as
they come in contact with the diaphragm.

page_text: The heads, s, s¹, of the triple-valve may be perforated or provided with openings
in order. to permit the escape of exhaust or leakage.
The chamber, q, of the triple-valve has an outlet, t, connected by a branch-
pipe, t, with the brake cylinder, and the openings in sach outlet are preferably
contracted in order to so control the air as to permit the brakes to set gradually
and release rapidly and this purpose may be further subserved by making these
outlets smaller at their ends within the valve than at their ends within the
pipe, t¹.
:
The operation is substantially as follows:-
The engineer's valve, B, being in the position shown in full lines, the air from
the main reservoir passes through the line of pipes, F, into the auxiliary reservoir
and into the triple valve and acting against the piston, », drives it past the outlet, t,
and so permits the air to pass into the brake cylinder and set the brakes. It will
be observed that the air goes straight from the main reservoir to the brake
cylinder and that the supply of air is constant so long as the pump is going, so that
in going down grades the run may be continuous and under constant pressure of
the air on the brakes and thus the necessity for frequent stoppings to refill the main
reservoir and the auxiliary reservoir are avoided. When it is desired to release the
brakes, the engineer's valve is thrown over into the position indicated by dotted lines
(the handle, k, of the valve being then in the position shown at, 2,) whereby air will
pass from the main reservoir into the pipe, G, as well as into the pipe, F, and
entering the triple-valve through the pipe, o, under equal pressure will meet the
larger area of the piston, r¹, and thereby move the said piston, and, of course, the
piston, ?, so as to pass the outlet, t, in the other direction and permit the air from
the brake cylinder to flow out of the chamber, y, through the perforated head, s, into
the atmosphere, and thus permit the spring, v, or other device, to release the
brakes.
Should the train break while the brakes are on, and the engineer's valve is in the
position shown in full lines, then the check-valve, m, would be seated and the pressure
in the auxiliary reservoir would serve to automatically set the brakes.
Thus provision is made for working the brakes by straight air, and also automatically,
as those terms are commonly understood in this art.
To again seat the brakes after having been once released and the train being
intact, the engineer's valve is moved into the full line position which cuts off the
supply of air to the pipe, G, while continuing it to the pipe, F, and at the same
time, opens the pipe, G, through the port, i, to the outlet, j, and the atmosphere,
thus taking pressure off of the piston, 7, and again permitting the air to work
through the auxiliary reservoir and pipes to triple-valve upon the piston, r.
As will be observed, the triple-valve is of exceedingly simple construction, and
the operation being positive and direct, the brake system becomes one of great
simplicity and great power.
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―
First: A straight air automatic brake, comprising a main reservoir, two lines of
pipes, an engineer's valve interposed between the main reservoir and the two lines
of pipes and having a port to open communication between the main reservoir and
one or both lines of pipes, and another port to open communication between.one line
of pipe only and the atmosphere, an auxiliary reservoir, a triple valve comprising
two pistons moving together and of unequal area and arranged in isolated chambers,
the smaller piston and chamber communicating directly with one of the lines of
pipes and the auxiliary reservoir and with the brake cylinder, and the other chamber
..containing the larger piston communicating with the other line of pipe and the
atmosphere substantially as described.
Second: A triple-valve comprising a shell divided into compartments isolated from
one another and of unequal area, and pistons of corresponding unequality as to

page_text: area arranged in the said compartments or chambers and rigidly connected by a
stem common to both, combined with two lines of pipes both of which are adapted
to be put into open communication with a main reservoir and one of which is always
in such communication, and is also open to the smaller chamber of the triple-valve
and thence to the brake cylinder to set the brakes, and the other of which opens into
the larger chamber of the triple-valve and may be opened to the main reservoir to
release the brakes and then opened to the atmosphere to permit the escape of the
air for permitting the setting of the brakes, substantially as described.
Third In an air brake system, the engineer's valve for use in connection with two
lines of pipes, comprising a plug having a port adapted to open communication
between the air supply and either or both lines of pipes and another port for
exhausting the air from one of the lines of pipe into the atmosphere, substantially as
described.
:
Fourth A triple-valve composed of two chambers of different area and provided
with corresponding pistons, the chambers and pistons being isolated one from the
other, and the pistons being connected by a stem common to both, a connection of
the smaller chamber with the auxiliary reservoir, and an independent connection of
said chamber with the brake cylinder, and an exhaust for the brake cylinder in said
smaller chamber, and a connection of the larger chamber with the main reservoir
and with the atmosphere, substantially as and for the purpose specified.
:
Fifth A triple-valve composed of two chambers of different area and provided
with corresponding pistons, the chambers and pistons being isolated one from the
other, and the pistons being connected by a stem common to both, a connection of
the smaller chamber with the auxiliary reservoir, a check-valve interposed in a branch-
pipe connecting the auxiliary reservoir with the main line of pipe, and an independent
connection of said chamber with the brake cylinder, and an exhaust for the brake
cylinder in said smaller chamber, and a connection of the larger chamber with the
main reservoir and with the atmosphere, substantially as and for the purpose
described.
Dated this 1st day of October
1000
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.