Improved Means for Preventing Accidents on Railroads.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improved Means for Preventing Accidents on Railroads.
I, JOHN BATTEN MITCHELL, of 13, Alma Road, Westham, in the Town of
Weymouth, in the County of Dorset, one of the Counties of England, Great
Britain, a Watch and Clockmaker by trade, do hereby declare the nature of this
invention to be as follows:-
My invention consists of mechanical contrivances worked from one source auto-
matically for preventing a certain form of railroad collision, such collision being
produced by a block on the line caused generally by a truck, train, or locomo-
tive, remaining, and thus allowing of another train travelling on the same
line running into it.
This I effect by making the unshunted blocking train or truck to actuate by
its own weight, automatically, two distinct and separate safety devices---one
for shutting off the steam of the travelling train and simultaneously putting on
the brakes thus bringing it to a stand still and preventing collision, and, the
other, for raising the danger signal and giving warning in due time. Thus
I cause by this arrangement the obstructive or dangerous element to be not only
its own preservative, but that of all others travelling on the same line to that
particular spot..
In order to arrange this I make at a station or well known shunting place
a portion of the permanent way equal to about the length of a locomotive a
raised movable platform. This platform fits into the space between the rails
of the general line, flush, close up to them, and is so constructed that on the
weight of a truck, or train, or locomotive resting on it it will immediately
sink to a level sufficient to cause the mechanism attached beneath it to actuate
by means of connecting rods at a considerable distance away both a hinged plate
that engages a mechanical arrangement fitted to the throttle valve as well as to
the brake gear of a locomotive whereby the steam is completely shut off, the
brakes put on, and the engine brought to a stand still as soon as possible thus
avoiding collision, and, also, at the same time, this same sinking process is made
the means by another mechanical device of raising the danger signal at the
proper station, and of giving warning in due time.
Fig. 1 represents a longitudinal vertical section of a portion of the permanent
way of a railroad fitted with this movable platform through the guide rods I, 1,
the platform having a blocking load in the shape of a locomotive.
Fig. 2 is a plan of the permanent way fitted with this movable platform.
part being shown in section & part broken away to show the mechanism
beneath.
Fig. 3 is a perspective view to an enlarged scale of part of the front of the
firebox of a locomotive showing the mechanism embodying my invention for

page_text: shutting the throttle valve, and also for putting on the air brakes to a travelling
locomotive.
"
Fig. 4 is a front vertical elevation of a signal post provided with the
mechanism embodying my invention for raising the danger signal to a passing
locomotive, the line being blocked.
Fig. 5 is an end view of Fig. 4 wherein the details of my invention are
shown.
Fig. 6 represents a longitudinal section of a portion of the protecting cylinder
encasing the connecting rods that are actuated by the movable platform.
Fig. 7 represents a longitudinal section of the rods afore mentioned showing
the arrangement of connections for allowing of expansion and contraction.
The platform P is made about the length of a locomotive and is constructed in
the strongest manner possible of wooden beams braced with iron clamps so as
to bear the strain and continued wear and tear. In its normal condition it
rests just about on a level with the rails, close up to them so as to catch
the flanges of the tires of the wheels of any train. The ends are bent down
towards the permanent way so that a truck or train may readily mount without
obstruction, and thus when a load is on this portion of the line part of the
weight is taken by the fixed rails and part by the movable platform. In order
to meet the unusual strain on the wooden edges that receives the tire flanges
they are faced with iron or steel plates. On the lower portion of the platform
and near each corner massive shafts or rods I, I, are let in and firmly fixed to
the wooden part of the framework. These rods are arranged to fit truly into
cylinders or sockets s, s, s, s, that are sunk into corresponding four corners of the
brickwork of a pit A A made to receive the platform 1', so that these rods in
moving up and down in these sockets act with them as guides to the platform
in its movements causing it to rise and fall in a vertical direction. At the
bottom of each socket s is a thick spiral spring w. These four springs so placed
are of sufficient power to hold up the platform P to the raised position (see
dotted lines Fig. 1) when there is no load on it as heavy as the lightest truck
on the line, but when such a load, or heavier one comes on to the platform,
the springs w, w, w, w, double up and fold together so as to rest with the rods I,
and socket bases as a part support to the weight, and allow of the platform being
brought down to the position shown in drawing Fig. 1, for at no time will the
springs bear the weight of the entire load.
The sinking of the platform P actuates the mechanism connected with it con-
sisting of the following parts and arranged for the purpose of preventing any
other train running into the blocking load. A smaller pit faced with brickwork
or concrete is also constructed being a continuation down from the platform pit,
and is made large enough to receive this mechanism and admit of its free move-
ments. This mechanical contrivance consists principally of three levers and a
fixed shaft connected and arranged with one another and the platform 1', so as
to convert the up and down movements of the platform vertically into direct
horizontal movements for actuating the safety mechanism.
At the centre of the base of the platform 1', a strong bearing plate B is
fixed. To this bearing B is bolted one end of a lever arm N, the other end
being similarly fitted to the lever K. The other end of this lever K is keyed
on to a shaft L that pivots in bearings let into the brickwork of the lower pit.
This shaft carries also another lever Q keyed on to it about at right angles to the
direction of the arm K and so placed that one end of it q may rise beyond the line
of rails and somewhat above them. To this end g, of the lever Q, two rods R, R',
are fitted. These rods R, R¹, run alongside of the permanent way for a con-
siderable distance, and are similar to those at present in use for signalling, and
are placed for protection in sheet brass cylinders, or wooden troughs C, C, such
that will readily admit of the examination or adjustment of these rods when
required:
The rod R is connected to my mechanical device for shutting the throttle valve

page_text: апи
is
putting on the air brakes of a travelling locomotive, and the rod R',
connected to a contrivance for raising a danger signal independently of the
apparatus that may at the time be in general use for such purpose.
The first part of this safety device consists of a thick metal plate F, that
5 hinges on a fixed shaft f fitted into bearings or suitable stanchions outside
each line of rail of the permanent way. This plate is never allowed to rise
sufficiently high in pivoting on f, to touch any portion of the machinery or
firebox of a passing locomotive although it is placed centrally between the
metals. Close to where this plate F is placed the rod R terminates, and has
O this end fitted to a lever v. This lever vis keyed on to a shaft u, placed as shown
beneath the rails, and this shaft u has a cam 7 keyed on to it in a position to lift
the plate F. Supposing the rod R to be pulled out by a blocking load on the
platform the cam will be made to raise the hinged plate F.
The throttle valve lever D, at present in general use is provided with an addi-
tional arm E at right angles to it. This arm E is slotted nearly its entire
length d, d. A strong steel shaft or rod S, carrying at its lower end a roller
wheel W, is made to engage this slotted lever E by means of its upper end
being provided with a brace sliding bolt g, which joins the two together as
well as to a vertically fixed set of guide bars n, n, rivetted to the front plate
of the firebox. To cause this rod S to move vertically in engaging the arm E,
and also to strengthen it in its movements it is provided with another guide in
the shape of a stanchion rivetted to the firebox plate in the same manner as the
set of bars n n.
When the roller wheel W of this rod S meets the raised inclined plate (as
shown in Fig. 3) by reason of a locomotive travelling over it, and a blocking load
being also already on the platform P, this roller wheel W will run up the plate. F,
and, in running up, will cause the rod S to turn round for a certain distance
the attached arm E by means of the connecting sliding bolt g, and it does not
cease to turn it till the throttle valve has been completely closed.
Also, in a similar manner, another arm El attached also to the throttle arm D,
and also to the brake gear arm D¹ by a sliding bolt g¹, is made by this same
rod Sg to turn round proportionately with the throttle arm E, so that when
the steam has been completely shut off the air brakes are as full on as when
operated by hand in the usual manner.
Thus by this arrangement the blocking load on P, pulls out the rod R, this
actuates at once the lever to which it is attached v, and causes the cam, on
shaft u, to raise the hinged plate F, this plate is raised, the travelling loco-
motive running over it has by means of the rod S, levers E, D, the steam shut off,
and the danger of a collision is averted and to make the stoppage more certain
the red S also actuates the levers E¹, D¹, of the air brake gear G, which which
mmediately put on the brakes.
The second part of my invention relates to a contrivance for raising a danger
ignal either by day or night independently of, and not interfering with the
sual arrangements placed for such purpose on the line.
This arrangement is brought about by the same sinking of the movable plat
orm P, which sinking is necessarily caused only by a dangerous obstructive load
n the line. The second rod R-also actuated by being attached to the lever Q
f the platform P-has its further end fitted to a wheel H. By the same fasten-
g bolt another rod similar to one of the lengths R, R', is fitted at y. This
od J reaches up vertically to the signal raising mechanism. This consists of
vo levers o, and o¹. The lever o pivots on a small shaft b, fixed in the frame-
ork of the signal post. The shorter arm of this lever is connected to the upper
ad m, of the rod J. The longer arm terminates in a hook piece c.
fixed by bolts at one end to the signal plate itself so that it pivots conjointly
The lever o¹
ith it on the same bearing a. The other end of this lever ol is bent so as
rest in the hook piece of the lever o.
When then the rod R' is pulled out it turns round the wheel H and moves

page_text: the rod J from the position shown in dotted lines in Fig. 4, this causes the lever o
to rise, proportionately carrying by means of the hooked piece c the lever o¹
upward, and, consequently, along with it the danger signal so that a warning
may be given in due time.
As each rod R', R¹, may extend about a mile in length, each length-which
may correspond to that of the rails-is provided for the necessary expansion
and contraction by having at each length-end a button t, t, that fits losely into
a short tube-piece or jacket e. Into each end of this tube piece e is screwed a
socket collar h, h¹. These collars hold the lengths in place. In expansion the
buttons t, move towards each other. The movements of the platform P take
up the slack.
In witness whereof I have hereunto set my hand the 28th of Tule 1800
Improved Means for Preventing Accidents on Railroads.
JOHN BATTEN MITCHELL, of 13, Alma Road, Westham, in the Town of
Weymouth, in the County of Dorset, one of the Counties of England, Great
Britain, by trade a Clock and Watchmaker, 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:-
My invention consists principally of certain mechanical devices so constructed
and designed as to be workable from one source automatically for the purpose
of preventing a certain form of railroad collision such collision being produced
by a block on the line caused by a train, or locomotive or truck being inadver-
tently left there, and thus being the means of causing probable loss of life or
serious damage to property by allowing from such neglect of another train
travelling on the same line running into it.
This I effect by making the. unshunted blocking train or truck to actuate by
its own weight automatically two distinct and safety devices one for shutting off
the steam of the travelling train and simultaneously putting on the brakes
thus bringing everything to a standstill and preventing collision, and, the other
for raising the danger signal and giving due warning of the obstruction. Thus
I cause by this arrangement the obstructive or dangerous element to be not
only its own preservative, but that of all others travelling on the same line to
that particular spot.
In order to arrange this I make at a station or well known shunting place a
portion of the permanent way equal to about the length of a locomotive a
movable platform. This platform fits into the space between the rails of the
general line flush with and close up to them, and is so constructed that on a
truck, train or locomotive resting on it so as to give part of its weight by
means of its wheel flanges depressing it, it will immediately sink to a level suffi-
cient to cause the mechanism attached beneath it to actuate by means of con-
necting rods at a considerable distance away both a hinged plate that engages
a mechanical arrangement fitted to the throttle valve of the locomotive as well as
the brake gear of the same whereby the steam is completely shut off, the brakes
put on, and the engine brought to a stand still as soon as possible, thus avoiding
the impending collision. Also, at the same time, this same sinking process of
this platform is made the means by another mechanical device of raising the
danger signal at the proper station, and of giving the necessary warning in due
time.

page_text: when the block ceases by the load moving off the platform so that the line there
is again clear, the platform rises again to its normal position, and in so doing
allows the hinged plate to drop automatically by its own weight, and at the
same time lowers the danger signal, so that this part of the line is also rendered
5 clear both as to the raised hinged plate and danger signal.
With reference to the drawing filed with the Provisional Specification, and
the drawings on Sheet 1, and Sheet 2, filed with the Complete Specification:-
Fig. 1 represents a longitudinal vertical section of a portion of the permanent
way fitted with this movable platform and through the guide shafts I, I, form-
ing part of this platform. The platform being shown with a blocking load
on it in the shape of a locomotive.
Fig. 2 is a plan of the permanent way fitted with this movable platform, part
being shown in section, and part broken away to show the mechanism beneath.
Fig. 3 is a perspective view on an enlarged scale of part of the front of the
firebox of a locomotive showing the mechanism embodying my invention for
shutting the throttle valve and also putting on the air brakes to a travelling
locomotive.
Fig. 4, is a front vertical elevation of a signal post provided with the mechanism
embodying my invention for raising the danger signal to a passing locomotive-
the line being blocked.
Fig. 5 is an end view of Fig. 4, wherein the details of this part of my in-
vention are shown.
Fig. 6 represents a longitudinal section of the rods aforementioned in a
protected encasement, which encasement is however optional, the rods being to all
intents and purposes similar to those at present in general use for signalling, &c.
Fig. 7 is another view in section of the same rods at another portion of their
length.
Fig. 14, Sheet 1, is a vertical longitudinal section through the guide shafts
of the platform fitted to its pit; the one half to the right with load depressing
it, that to the left in its normal state.
Figs. 2 and 3 Sheet 1, represent respectively transverse vertical sections of
the platform shown in Fig. 1. In the view to the right a load is depressing
the platform and actuating all the safety devices which are also thereby locked.
Fig. 4 Sheet 1, is a plan of Fig. 1^, the top half being removed.
Figs. 1, 2 and 3 Sheet 2, represent respectively an end vertical elevation, a
side view, and a plan of a front portion of a locomotive fitted with my devices
for shutting off steam and putting on the brakes together with the con-
trivances fitted to the permanent way for actuating these & signalling by means
of the depression of the platform.
The platform P is made about the length of a locomotive and is constructed
n the strongest manner possible of stout wooden beams braced with iron clamps
o as to bear the strain and continual wear and tear and jarring. But I do
ot confine myself to this particular mode of construction as long as rigidity
uitable for the purpose is preserved. In its normal condition it rests on a
evel with the rails, close up to them, so as to catch the flanges of the wheels of
ny truck or train passing over it. The ends of the platform are bevelled down
or a considerable distance to meet at an acute angle the permanent way so that
truck or train may readily run on to it without obstruction and thus when
load is on this portion of the line most of the weight is taken by the fixed
ils and a certain sufficient part by the movable platform. In order to meet
e unusual strain on the wooden edges that receive the wheel flanges they are
ced with iron or steel plates.
On the base or under portion of the platform and near each corner massive iron
afts I, I, are let into and firmly fixed to the framework so as to form one
tire solid structure. These shafts are arranged to fit truly into cylinders or
ckets of cast iron s, s, s, s, that are embedded and fastened within correspond-
g four corners of the brickwork of a pit A A which is especially made to

page_text: receive the platform P, so that these shafts I, I, I, I, in moving up and down in
these sockets s, », s, s, act with them as guides to the platform in its movements,
causing it to rise and fall in a vertical direction.
At the bottom of each socket s, is a spiral spring w. These four spiral springs
so placed are of sufficient strength to hold up the platform P, to the position
shown in dotted lines Fig. 34, Sheet 1, about level with rails of the permanent
way when there is no load on it as heavy as the lightest truck on the line;
but when such a load, or heavier one, comes on to the platform, the springs
w, w, w, w, fold together so as to form with the shafts I, and socket bases a
support to the weight or pressure caused by the flanges of the wheels of the
blocking load. This allows of the platform being brought down to the position
shown in the Fig. 3, Sheet 1; for at no time will the springs bear the weight of
the entire load, but only a small portion of it comparatively,-being about a
little more than the weight of the platform itself.
This sinking of the platform P actuates the mechanism connected with it
consisting of the following parts arranged and combined with one another for
the purpose of preventing any other train running into the blocking load or
obstacle as hereinafter explained.
A smaller pit faced with brickwork or concrete is constructed in addition to
the pit A A, being a continuation of it,. on one side, and is made just large
enough to receive this mechanism and admit of its free movements.
This mechanical contrivance consists principally of three levers and a shaft
connected and arranged with one another and the platform 1', so as to convert
the up and down vertical movements of the platform into direct horizontal
movements for actuating the safety mechanism throughout, which may be
described as follows:-Referring to drawings:
At the centre of the base or under part of the platform a strong bearing
plate B is fixed: To this bearing B is bolted one end of a lever arm N, the other
end being similarly fitted to a lever K. The other end of this lever K is keyed
on to a shaft L, that pivots on bearings let into the brickwork of the lower
pit. This shaft carries also another lever Q keyed on to it about at right angles
to the direction of the arm K, and so placed that one end of it may rise beyond
or outside the line of rails. To this end, q, of the lever Q, two rods R, R¹,
are fitted.
These rods R, R, run alongside of the permanent way for a considerable dis-
tance and are similar to those at present in use for signalling. The protecting
cylindrical casings or wooden troughs e c may or may not be used on certain
portions of the line. As seen at present I do not consider that they are neces-
sary inasmuch as the signalling rods now in general use do not require them.
The rod R is connected to my mechanical device for shutting the throttle
valve and putting on the air brakes of a travelling locomotive, and the rod R¹ is
connected to a contrivance for raising a danger signal independently of the
apparatus that may at the time be in general use for such purpose.
The first part of this safety device consists of a thick metal plate F, that
hinges on a fixed shaft f, fitted into bearings or suitable stanchions outside
each line of the rail of the permanent way. This plate is never allowed to rise
sufficiently high on pivoting on f to touch any portion of the machinery or
firebox of a passing locomotive although it is placed between the metals. Close
to where this plate F is, the rod R terminates and has this end fitted to a lever v
(see drawings Figs. 3 & 2). This lever is keyed on to a shaft u, placed, as
shown, beneath the rails, and this shaft u has a cam 7, keyed on to it in a position
to lift the plate F.
The throttle valve D, at present in general use, is provided with an additional
arm E, at right angles to it. This arm is slotted nearly its entire length d d.
A strong steel shaft or rod S carrying at its lower end a roller wheel W is made
to engage this slotted lever E, by means of its upper end being, provided with
a brace sliding bolt which connects the two together. Guide bars n, n, rivetted

page_text: to the front plate of the fire box are provided for the same sliding bolt to move
in up and down vertically. Also to cause this same rod to move vertically in
engaging the arm E, and to strengthen it in its movements it is provided with
another guide in the shape of a stanchion-rivetted to the fire box plate in the
5 same manner as the set of guide bars n, n.
When the roller wheel W of this rod S meets the raised inclined plate (as
shown in Fig. 3) by reason of a locomotive travelling over it, and a blocking
load being already on the platform 1', this roller wheel W will run up the
plate F (which plate has been raised as an inclined plane by the cam (as herein-
after described) and in so doing will cause the rod S to turn round for a certain
distance the attached lever arm E by means of the connecting sliding bolt g, and
it does not cease to turn it till the throttle valve of the locomotive has been com-
pletely closed.
Also, in a similar manner another arm E, attached also to the throttle valve
arm D, and also to the brake gear arm D₁ by a sliding bolt g' is made by this
same rod Sg to turn round proportionately with the throttle arm E, so that
when the steam has been completely shut off for the running engine, the air
brakes are as full on, and with as full power as when operated by hand in the
usual manner.
•
Thus, by this arrangement the blocking load on the platform P pulls out the
rod R; this at once actuates the lever to which it is attached
the cam 7, on the shaft u to raise the hinged plate F. This plate being raised
v, and causes
the travelling locomotive running over it has by means of the rod S levers E, D,
the steam shut off, and the danger of a collision is averted, and, to make the
stoppage more certain, and impending collision impossible, the rod S is also
made to actuate the levers E¹, D₁, of the air brake gear G, which immediately put
on the brakes.
The second part of my invention relates to a contrivance for raising a danger
signal either by day or by night independently of, and not interfering with,
the usual arrangements placed for such purpose on the line.
This arrangement is brought about by the same depression of the movable
platform 1', which depression or sinking is necessarily caused only by a dan-
gerous obstructive load on the line.
The second rod Ralso actuated by being attached to the lever Q of the
platform P, has its further end fitted to a wheel H. By the same fastening
bolt another rod similar to one of the lengths R, R', is fitted at y. This rod, J,
reaches up vertically to the signal raising mechanism consisting essentially of
wo levers o and o¹.
The lever o pivots on a small shaft or pin b, fixed in the framework of the
ignal post. The shorter arm of this lever is connected to the upper end of
he rod J. The longer arm terminates in a hook piece c.
y bolts at one end to the signal plate itself so that it pivots conjointly with
The lever o¹ is fixed
t on the same bearing a. The other end of this lever o¹ is bent so as to rest in
he hook piece c of the lever o.
When then the rod R¹ is pulled out, it turns round the wheel H and moves the
od J from the position shown in dotted lines in Fig. 4. This causes the lever o to
se proportionately carrying by means of the hooked piece c the lever o' upward,
ad, consequently, the danger signal along with it, so that the requisite warning
given by this means automatically and in due time to prevent collision
hich is the object of this part of my invention also.
For the expansion and contraction of the rods R, R-which may in some
ses extend as much as a mile in length--the same connections for the several
ngths of rod are used as is now the general practice with those employed
signalling &c.
In Fig. 7 I have shown an arrangement for the same purpose consisting of the
lowing parts:-Each length is provided at each end with a button that
s loosely into a short tube or jacket e. Into each end of this tube piece e e.

page_text: is screwed a socket collar h h¹. These collars hold the lengths in place. During
expansion the buttons move towards each other.
It is evident from the description of the working of the platform by means
of the wheel flanges of a truck, train, or locomotive, and the like, that both the
hinged plate F and the danger signal are locked the entire time that such load is
depressing the platform and unlocked only when this weight is removed, and
platform returned to its normal position--the cam 7 being shut down by the force
exerted on the mechanism N QK L and rod R, by the rise of the platform.
On the depression of the cam 1, the plate F falls by its own weight, and the
rod R being also actuated in the same manner as the rod R-pulls down the
danger signal by means of the rod J, and wheel H, and the line necessarily
becomes again clear.
Having now particularly described and ascertained the nature of my said
invention & in what manner the same is to be performed I declare that what
I claim is
1. The automatic rising and sinking platform P, with connected levers N K Q
on shaft L and rod R, in combination with a locomotive's steam shutting off
mechanism described consisting essentially of the lever shaft with lifting
cam u,, respectively, hinged plate F, roller rod S W, slotted throttle arm E,
and sliding bolt g that travels in guide bars n, n, all arranged & operating
together substantially as and for the purposes herein set forth.
2. The automatic rising and sinking platform 1' with connected levers NKQ
on shaft L, and rod R¹ in combination with the danger signal mechanism des-
cribed consisting essentially of the wheel H, rod J, lever a c and lever o¹, fixed to
the danger signal plate, each and all arranged substantially as and for the
purposes herein set forth.
3. The automatic rising and sinking platform P with connected levers N, K, Q
on the shaft L, and rod R, in combination with the double lever in a locomotive's
air brake gear E¹ D¹ G and steam throttling mechanism E, D; roller wheel and
rod W S, plate F, lever arm, and shaft with lifting cam ul, respectively, all
arranged substantially as and for the purposes herein set forth and described.
4. The locking mechanism consisting of the wheel flanges of a load Z, in
combination with the automatic rising and sinking platform l, connected
levers N, K, Q, on shaft L, rod R, cam ul, lever v. hinged plate F with steam
shutting off mechanism S W and E D, and air brake gear E¹ D' G, and also
danger signal contrivance J H, o c, o¹, substantially as and for the purposes
herein set forth.
5. The double lever E, D, E D¹ G, in combination with the roller wheel and
rod W S, respectively, hinged plate F f, cam u 1, lever, and actuating rod R, all
arranged in the manner described, substantially as and for the purposes herein set
forth.
Dated this Twenty-eighth day of April in the year of Our Lord One