Improved Method of and Apparatus for Automatically Stopping Railway Trains.
Year: 1891

page_text: Date of Application, 24th Oct., 1891-Accepted, 28th Nov., 1891
COMPLETE SPECIFICATION.
[Communicated from abroad by PAUL RIBARD, of 58, Rue de la Chaussée
d'Antin, Paris, France, Engineer.]
Improved Method of and Apparatus for Automatically Stopping
Railway Trains.
I, ERNEST DE PASS, of 78 Fleet Street, in the City of London, Fellow of the
Chartered Institute of Patent Agents, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement, reference being had to the
accompanying drawings and to the letters and figures marked thereon, that is
to say:
This invention relates to an improved method of, and apparatus for, automatically
stopping railway trains without the intervention of the driver, by means of a device
or appliance termed a "tube-breaker."
The invention consists in modifying, as hereinafter explained the compressed air,
gas, steam and vacuum inlets which are employed in the working of Westinghouse,
W
enger and like brakes, and whether these inlets be automatic in their action or
otherwise. The essential feature of the invention consists in causing a fragile tube,
connected with the brake inlets, to be broken by striking against some hard body
the position of which is caused to vary according as the line is clear or is blocked.
I will first describe the invention as applied to brakes having automatic inlets,
that is to say those in which the pressure is produced simultaneously under all the
carriages as soon as the inlet is put into communication with the atmosphere.
A tube t (Fig. 1) made of glass, or other fragile substance, and closed at one
end, is connected to the tube I which is led directly to the automatic inlet. The
connection of the tube t to the tube T is effected by the screw-joint T' which
tightly presses the base or flange of the tube t between two washers r, r', (Fig. 2)
of rubber, or other material, thereby forming a hermetic joint, these two washers
being placed one in front and the other at back of the enlargement or flange with
which the tube t is formed at its base.
Thus the interior of the tube t, the tube T, and the automatic inlet, form together
one and the same passage or inlet. If the tube t be broken the automatic inlet will,
by reason of this rupture, be open to the atmosphere and the brakes will consequently
be applied and the train be stopped.
The hard body or weight M (Fig. 1) against which the tube t strikes, and by
which it is broken, must be very heavy in proportion to the surface which it offers
to the wind; by preference it is made hollow and of cast iron, and is filled with
lead. It is suspended by a chain passing over the grooved pulley p and wound
around and fixed in the groove d of a horizontal pulley P which has the same
axis of rotation as the signal A. Thus when the signal A is moved to
indicate whether the line is clear or is blocked, the weight M will rise or fall a
distance equal to a quarter of the circumference of the pulley P. The tube t is
arranged horizontally (Fig. 1), while the tube T forms an elbow and
passes down
alongside of the chimney of the locomotive, to which it is firmly fixed by one or
more collars, such as C. On reference to the traffic gauge shown by dotted lines
in Fig. 1 of the drawings it will be seen that if the signal be at danger the tube t
will always strike against the weight M and will therefore always be broken by
striking against such weight; but if the line be clear and the signal not at danger,
the weight M will be raised entirely above the traffic gauge and will allow the tube
to pass, and consequently the train.
If the signal A is situated too near to the obstruction which it covers, so that
the brake would not have time to act, the weight M, and the arm from which it is

page_text: suspended, can be placed at any suitable distance from the signal and be connected
thereto by a cable as seen at Fig. 1*.
I will now describe how the fragile tube may be adapted for stopping trains
which are not furnished with automatic inlets.
The following apparatus, on the breakage of the fragile tube, permits of an air,
steam, vacuum or other fluid inlet to be automatically opened and the fluid to be
directed into the conduit wherein it is desired that it shall act.
For example, let S (Fig. 3) be the valve to be opened so that the brake may be
applied. P is a piston which I call escape piston" (piston à fuites) because it is
.provided with three small grooves or channels a, b, c, which allow the fluid employed,
to pass from below to above the piston. It will be seen that so long as the fragile
tube & remains unbroken the piston P having the fluid pressure both below and
above it, will be held at the bottom of its stroke and be pressed by its stem onto the
valve S with which it forms an integral part. On the breakage of the tube ta
sudden depression is produced above the piston P which therefore quickly rises,
carrying with it the valve S, and thus allowing free passage to the fluid which now
passes into the pipe D, E, and actuates the brake in the same manner as if it had
been admitted by the driver through the pipe F, E.
The cock R (always closed) is for the purpose of ascertaining whether the
piston P is in good working order before the train starts; the cock R is always
open while the train is running. After the breakage of the tube t and the stoppage
of the train it is necessary to replace the broken tube by a fresh one, before again
starting, the cock R being kept closed during the replacing of the tube but opened
again when said tube is in place.
The cocks R' (Fig. 1) and R (Fig. 3) must always be kept open while the train
is running, and the driver must only close them when a broken tube is to be replaced
by a fresh one. It is therefore necessary to adopt an arrangement, such as that
shown in Fig. 1, which consists in securing the handle of the cock to a fixed point
by a sealed wire, so that the driver cannot close the cocks without accounting for
the breaking of the sealed wire.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I claim, as communicated
to me by my foreign correspondent.
1. The method of automatically effecting the stoppage of railway trains by the
rupture of a fragile portion of the brake inlet or pipe caused by its striking against a
solid body working in connection with the signal, substantially as herein described.
2. The means for automatically causing the rupture of the brake inlet or pipe,
consisting in the employment of a fragile tube connected with said brake inlet or
pipe and of a heavy suspended weight which is brought in the path of the tube by
the setting of the signal to danger and moved out of such path when the signal is set
to indicate that the line is clear, substantially as herein described and shown.
3. The special arrangement for causing the rupture of the fragile tube, consisting
in bringing forward the weight by means of a chain connected directly to a pulley
turning with the signal disc, and which chain passes over a guide pulley placed
perpendicularly to the path of the tube, substantially as described and shown.
4. The special arrangement of the "tube-breaker" for use in cases where the
signal would be situated too near the obstacle on the line to allow time enough for
the train to be stopped between the signal and the obstacle, substantially as herein
described and shown with reference to Fig. 1* of the drawings.
"
5. The special arrangement hereinbefore described for enabling the "tube-
breaker to be placed at any desired point on the permanent way so that its rising
and falling movement may be produced either directly by any well known means,
or by connection with a moving part of the signal.
Dated this 24th day of October 1891.