Improved Apparatus for Prevention of Collisions upon Railroads.
Year: 1894

page_text: Date of Application, 21st Aug., 1894
Complete Specification Left, 21st May, 1895-Accepted, 21st Aug., 1895
PROVISIONAL SPECIFICATION.
Improved Apparatus for Prevention of Collisions upon Railroads.
I, REGINALD HADDAN of the Firm of Herbert Haddan & Co. Patent Agents
of 18 Buckingham Street Strand W.C. London in the County of Middlesex
Civil Engineer do hereby declare the nature of this invention a communication to
me from abroad by Frédéric Robine of Barc in the Department of Eure, in the
Republic of France, Mechanician, to be as follows:-
This invention is intended to prevent collisions between trains upon railroads
and the apparatus comprises certain double and single rotary dogs or frames as
hereinafter described to be operated by the trains passing over them or otherwise
and to cause the stoppage of any following train that may arrive within dangerous
proximity to a previous train on the same line of rails. The double dogs are
arranged at the entrance and exit of each station or usual stopping place at from
four to five hundred yards apart to allow of the trains stopping between them;
the single dogs are placed about four hundred yards beyond the aforesaid double
dogs. On the locomotive there may be placed two spring actuated levers to be
operated by said dogs or one of said levers may be arranged on the locomotive, the
other on the tender.-
The two. dogs. constituting the double dog are separated from each other by an
amount bearing a proportion of thirteen to twelve to the distance separating the
two levers on the locomotive or on the locomotive and its tender. The springs on
the levers are sufficiently powerful to overturn the dogs which are adapted to be
turned down in the direction in which the train is moving but will give to allow
the levers to pass over those dogs which oppose resistance in the direction aforesaid.
The double dogs are connected by a rod so that the depression of one lifts the
other. Each of the double dogs is composed of a frame hinging loosely on a hori-
zontal shaft which may also be turned and the dog engages and revolves the
shaft in one direction by means of ratchet and pinion gear. Each of these double
dogs may be fitted with an electric alarm to indicate to the engine driver or others
that the apparatus is acting effectively.
If a train passing in one or other direction, for instance from left to right is
followed by another train in the same direction too closely the dog on the left being
closed, operates, owing to the opposition of the ratchet on the key of a special
cock on the locomotive of the following train thus not only setting the automatic
brakes in action but reversing the steam to the piston and closing the throttle
valve.
The single dog is of the same general construction as the double dogs, but is
fixed on its shaft. It is intended for crossings and points and is placed from
four to five hundred yards from the points and is adapted to lock the points
so that the latter cannot be moved until the dog has been raised thus blocking
the line.
Dated this 21st do of Avianet.1894

page_text: COMPLETE SPECIFICATION.
Improved Apparatus for Prevention of Collisions upon Railroads..
1, REGINALD HADDAN of the Firm of Herbert Haddan & Co. Patent Agents
of 18 Buckingham Street, Strand, W.C. London, in the County of Middlesex,
Civil Engineer, do hereby declare the nature of this invention a communication
to me from abroad by Frédéric Robine of Barc in the Department of Eure,
in the Republic of France, Mechanician and in what manner the same is to be
performed to be particularly described and. ascertained, in and by the following
statement:
.
The object of this invention is to prevent collisions of trains due to the
negligence or forgetfulness of railway officials or to the inadvertence of drivers of
trains, so that a collision in this respect is absolutely impossible. In fact accidents
of this kind occur as often through the fault of the conductors or other train
officials, as in consequence of the negligence of signalmen. Those in charge of the
locomotive may be unable to see the signals at all, or only see them indistinctly,
or they by some accident may have been disabled.
The present invention prevents such accidents as may arise from carelessness
or any other cause in relation to the signalling.
Having underneath the locomotive an arrangement or device which will command
the Westinghouse brake, and the inlet of steam to the cylinders without interfering
with the ordinary gear attended' to, by the engine driver it is then necessary to
have along the track some other arrangements by which a train can automatically
he stopped, when the track is blocked even against' the will or intention, of the
engineer to do so, and which when on the contrary the track is free, would insure a
safe passage to the succeeding trains. A certain length of track in front of these
trains is at all events protected by the preceeding train inasmuch as an official must
have an express intention to permit a train to pass; the idea of negligence or
omission thus being done away with.
The apparatus hereinafter described comprises two sets of devices, the one to be
attached to the locomotive, the other to the track..
The arrangements made on the track comprise double and single dogs: the former
being placed on each track, on both sides of the station at a distance of about
500 metres, the others a little further at 300 to 400 metres from the double dogs.
(A single deg is provided for each double dog:). At the exit end of the station the
single dog may be dispensed with except for single line' railways taking trains in
both directions. The double dogs are controlled from the station, the others By
means of levers placed near to the double dogs, single dogs are also provided where
tracks branch off, and are controlled by interlocking with the switch or point lever
of such branch track.
I will first describe the mechanism on the locomotive.
This mechanism consists of:-
::.
..
.-
1. A curved arm or lever Q with spring g and a retaining pin n placed in front
in the direction of the running train.
2. A curved lever H governing a piston I' with the aid of special devices
actuating the vacuum brake and at the same time stopping the steam inlet to the
valves, and in case of necessity thus stopping the engine, when the train is not
provided with vacuum brakes.
3. A curved lever Q1 similar to Q above mentioned but placed in the reverse
direction behind lever H, for backward running.
Of these two levers, Q, Q¹ only one operates at a time, Q on the forward, Q' on
the backward run, that which is to remain inactive being beforehand raised and
suspended at a certain height by means of the bolt n or n¹.
What I denominate the curved lever is to a certain extent nothing but a bar Q,

page_text: pressed down by a spring 9 and movable about a hinge. The force of the spring
is calculated to be such that when the lever strikes a movable or elastic object, it
overturns it, when on the contrary it strikes a fixed object it glides over it thereby
compressing the spring g and the impediment in question remains in place and acts
upon the lever H, which in consequence communicates the pressure or movement
to the piston II, remaining in the position which it is now caused to assume
through the action of the two spring detents K, K', that are arranged in the frame
or strap-iron. The piston II (Fig. 5) is so constructed that the ports e e' of the
piston proper will communicate with, or place themselves in front of the ducts h h'
of the cylinder, when pushed upwardly to a certain distance. At this instant the
steam passing through the pipe J' acts upon the brake, while the steam passing
through pipe J stops the inlet into the cylinders.; in consequence of the action of
the steam passing through pipe J, piston K' is pushed forward and consequently
also the hollow piston L, which stops, the mouth of the pipe M' that leads to the
6 cylinder. Moreover for freight trains and the like not provided with vacuum
brakes the steam may be sent forward and backward or reversed in the large
cylinders; for this end! leave open the cocks of the pipes N. N. the mouths of
which correspond with the ports ff of the piston L, when the latter is pushed
forward through the action of K, then the steam that passes through pipe M.
cannot pass to the slide-valves but, running through pipes N. N. finds its way into
the large cylinders on both sides of the piston by the stopping of which, the train
also stops. But for passenger trains, and those fitted with Westinghouse brakes
the cocks of the pipes N. N, should remain closed.
The piston 1. could be replaced by a cock P such as shown in Fig. 3. The
communication of the ports and the tubes is obtained by turning the plug by the
aid of the lever arm P¹. The latter should preferably be made of whale-bone or
the like with a metallic core bar.
I will now describe the mechanism of the arrangement in connection with the
track.
As already mentioned on each track there are placed two double dogs, one at
a distance of 500 metres in front of the most forward switches (or points) at a
station or stopping place, the other at the same distance beyond the most rearward
switches, in order to permit of mauœuvring trains of greater length between said
switches and dogs.
The double dog (Fig. 1) comprises two frames A and B, the former movable
about the shaft A', the latter about B', each of which shafts is provided with a
counterpoise p. p. These two frames are united by means of rods b₁ b', the extremities
of said rode being pivoted to the extension of the shafts a and b. The dog is so con-
structed that when the frame A is in a vertical position, B is horizontal, and vice-
Moreover it may be observed from the position of the counterweights p. p.,
that the equilibrium of the whole is nearly unstable, or, at any rate may easily be
upset. To impart to the frictional parts a greater softness the shafts a and b may
be rollers with a covering layer of caoutchouc.
versa.
The toothed pinion Ŕ is connected with the frame A, a catch C having a
tail-end C, engages with or frees the said pinion R according as it is actuated by
the arm T which is solidly fastened to the shaft A¹.
To this shaft A' about which the frame A turns the counterweighted lever S is
keyed, it being operated from the station by a connection with lever c, there is
further an arm a attached to said shaft the object of which is to raise the frame A
to its initial position. The operating hand lever c at the station should always be
vertical and the bolt e' by which it is supported be placed in the upper notch.
Supposing the normal position of the dog A, B to be that shown in Fig. 1, it is
necessary that after it has been overturned by a passing train, it be reinstated in
the position illustrated (although only at the moment when the train is due) when
the station official knows his station to be free. For this purpose the lever c
has to be lowered to cause the shaft A¹ to lift the frame A and then immediately
raised again to its vertical position, as shown, in order to leave the connecting

page_text: wire to lever S slack to permit the dog to be again overturned by the next train
following in the same direction.
On socket d of lever e. there is also arranged a second notch for keeping the
lever cat such an angle that the lever S may cause shaft A" to sufficiently turn
to disengage the catch C. This position allows a train to run forward and back-
ward, as for instance for shunting purposes, since it enables the train to freely
overturn the dog, first in one and then in the other direction alternately-I may add
that the distance between frames A and B of the dog is 'much greater than that
between the curved levers Q and H underneath the locomotive. This condition is
necessary from the mode of operation of my system.
The station is supposed to be situated near the lever c (Fig. 1) the running
direction being indicated by the arrow.
The apparatus are placed on either side of the station in the same sense, but the
one part is regulated by means of a direct wire, the other by a double or returned
wire (see Fig. 4). Besides, it is well for double dogs to supplement them by an
electric bell work to thus ascertain the certainty of their working.
The arrangements are assumed to be as shown in Fig. 4, the descending line
having the direction indicated by arrows, and the dogs the position shown in Fig. 1.
A train leaves the station and the engine passes over the dog A B whereby the
lever Q strikes frame A thus overturning it and raising B into a vertical position
without the lever H being touched. Consequently the train passes freely and the
succeeding trains are protected by frame B, now raised.
If another train passes in the same direction without the dog A B being brought
back to its normal position, the device on the locomotive would strike the frame B
(which cannot be lowered towards frame A) and consequently the lever Q would
pass over without moving the frame and the said frame B would act upon the
lever H. Each train, therefore, that happens to pass against schedule time, which
time is indicated by frame A being raised, would be stopped automatically. The
station is also closed against a train entering the station at that end without
permission, since, owing to the catch C and to the pinion R, the frame A is kept
downwards until the lever c has been operated, and consequently frame B cannot
assume its initial position. It would therefore stop a train running back, the
approach of which was not signalled. As already explained when a train is to be
allowed to pass back, it is only required to disengage the catch by placing the
bolt c¹ of the lever c in the position (at an angle of 30 degrees) causing the
rotation of shaft A sufficiently to free the pinion R.
Supposing now another train to enter the station, always in the direction shown
in Fig. 4. When the track is open (the left hand double dog in the position of
Fig. 1) the train passes, thus covering the succeeding trains, as explained; if on
the contrary the track is not fiee, a train arriving thereon is instantly stopped
before entering the station. In this event it is intended that the driver should
descend from the engine in order to operate a lever that he will find near him on
the track (Fig. 4) commanding a small dog D, 400 or 500 mètres behind, so that
the track to the rear is protected. When the track is free the driver puts back the
said lever which lowers the dog; then disengages the spring H, drawing in the
handles and again starts. Lastly a traiu may have just started and the track
being vacant a train may arrive without its driver. In this case the train will
enter and pass through the station but will be arrested at the dog at the exit there-
from, frame B acting upon lever H.
For secondary stations or those where there is no night signal service it is
necessary after the passage of the last train to uncouple the double dogs which
permits them to be brought out of action and the track is free. In the morning
the two rods 6' are again coupled up before the passage of the first train.
Fig. 2 shows also a lever commanding a single dog placed in a track, which lever
interlocks with the switch or point lever of a branch track. As will be easily
understood on reference to the drawings the device prevents collision with a train
passing to or from the branch track when shunting.

page_text: g
Supposing that it is desired to move the point lever G', the box 9 receiving the
bolt of lever E can only be moved when the lever E has been lowered, that is to
say when the adjacent track is covered by the dog D, this dog arresting auto-
matically any train entering the station from that direction.
This system may be applied also to electrical engines. It is only necessary to
replace the piston I I¹ by a rod, of which vertical movement will interrupt the
current and throw on the brakes.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed I declare that what I
claim is :-
The apparatus for automatically arresting trains on a railroad when the line is
blocked and allowing them to pass when the line is free, consisting of devices on
the locomotive adapted to operate the brakes, cut off the steam from the valves and
turn the steam directly into the cylinders and means for operating said devices.
comprising the single and double dogs arranged as described.
Dated this 21st day of May 1895.
R. HADDAN.