Improvements in Apparatus for Signalling on Railways.
Year: 1896

page_text: Date of Application, 13th Oct., 1896-Accepted, 30th Jan., 1897
COMPLETE SPECIFICATION.
Improvements in Apparatus for Signalling on Railways.
I FRIEDRICH WILHELM PROKOV, Engineer, of 14 Reismühle, Hamburg, in
the Empire of Germany, 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:-
This invention relates to that class of circuit closers which are automatically
operated by a railway train, the flexion of one of the rails, caused by the weight of
the train, being communicated to an unequally armed lever, which, directly or
indirectly, closes the signalling circuit.
The object of this invention is to provide a special arrangement of such an
apparatus, and, further, the combination of two such apparatus, in such a manner,
that the one apparatus, on the passage of a train in one direction, causes the
terminals or contact pieces of a signalling circuit to come into contact, while the
other apparatus, on the passage of a train in the opposite direction, will prevent
the contact of the same terminals.
In the accompanying drawings, the said special arrangement is illustrated, and
the combination above characterized is represented in two practical forms.
Of the first form,-
Fig. 1 is a side view of a line of rails, with the combined apparatus adapted
thereto; and
Fig. 2 a plan view of the same.
Fig. 3 is a vertical section on an enlarged scale, taken on the line 1-1 of Fig. 2 ;
and
Fig. 4 is a vertical section through the contact maker and its enclosing casing.
Fig. 5 is a side view, partly in section, of a line of rails, with a modified form
of combined apparatus,
Fig. 6 being a plan view of the same.
Fig. 7 is a vertical section on the line 2-2, Fig. 6; and
Fig. 8 is a similar view on the line 3-3, Fig. 6.
Fig. 9 is a side view, partly in section, on an enlarged scale, of a modification of
the apparatus shown at Fig. 7; and
Figs. 10, 104, 10B are details which will be more fully referred to hereafter.
Referring now to Figs. 1, 2, 3, and 4, the apparatus combination consists of two
actuating devices arranged on the same rail at a certain distance apart, and
constructed exactly alike, so that only one needs to be described. On either side
of, and parallel with, a rail, as seen in Fig. 2, is laid a shaped piece of iron a.
These pieces of iron a, which lie across two adjacent sleepere, so as not to be in
contact with the latter, are connected at their ends, where they project over the
sleepers, by angle irons b, so as to form a frame. This frame carries at its middle,
und on its underside, a closed casing screwed thereto (see Fig. 3). In that
portion of the top of the box o which is between the frame, there works freely,
immediately below the foot of the rail, a bolt d, the upper end of which rests
against the foot of the rail. At its lower end, this bolt rests upon a projection e
formed on the boss of the lever f, and radially to the pivot pin g. A projecting
boss in the top of the box is surrounded by a rubber ring h, which prevents the
penetration of dust and moisture between the foot of the rail and the bolt d. The
projection e, on which the bolt rests, constitutes the short arm of the lever f
he longer arm terminating in a ball, which takes into a recess in the rod of a

page_text: k
piston i, provided at its centre with a suction valve. The valve plunger slides in a
cylinder formed in the casing c, and, if the rail is not depressed or deflected, is held
in its lowest, or normal, position, by a spring & acting on the longer arm of the
lever f. The spring k also so operates that the bolt d is always pressed up against
the foot of the rail. Upon the rail being depressed by the train passing over it, the
long arm of the lever f, through the action of the bolt d and projection e, lifts
the valve piston i. The piston thus raised forces the air which is above it, through
an adjustable valve in the cylinder cover m, into a passage n, and thence into the
pressure or delivery pipe o connected therewith. After each depression, the rail
rises again, the spring k causing the valve piston to descend, so that a fresh supply of
air is drawn in, which air, on the next lift or stroke, is forced into the pressure
pipe.
The pressure pipes o of both these, what may be termed pumping apparatus,
arranged one behind the other, are carried to a hollow standard p, Fig. 1, in which
they are led upwards into a hood or cap q (see Fig. 4), so as to be protected by the
éaid standard and cap. Each of the pressure tubes o terminates in a casing r,
between the two parts of which is fixed an air tight flexible diaphragm s. At the
opposite side of the diaphragm, and in a line with the pressure tube, is a pin t, which
projects through a boss in the casing, and operates a pivotally suspended lever u.
The two diaphragm pins t face each other, and the two levers u are situated
between them, each of the said levers u being kept pressed against its pin t by a
spring.
When the right-hand pumping apparatus in Fig. 2 is operated by a train or a
single vehicle passing over it, the air, in its pressure pipe o, the end of which is,
in Fig. 4, at the right-hand side, is compressed by the operation of its corresponding
valve piston, so that the diaphragm blocking the pipe o is distended to the left, and
its pint and the lever u moved to the left. The free end of this lever u operates
a bell-crank lever u, pivotally mounted on the right-hand casing r, and rotates this
bell-crank until the horizontal arm of the hell-crank presses on a lateral projection w
of the opposite lever u connected to the aerial line wire . The signalling circuit
is thus completed, the pressure tubes constituting the earth return. For increased
safety, a line wire may be connected to the buried pressure tubes, which wire leads
into the under-ground water.
The train, as it proceeds, then operates the second pump apparatus, the lever u
of which is moved outwardly, so that the projection of the latter, slides upon the
raised arm of the bell crank v, thereby securing a good sliding contact and keeping
the contact surfaces bright. The projection to is of such length, that it cannot slip
off the lifted arm. The circuit thus remains completed without interruption, till
the last wheel of the train has passed over both pump apparatus, and the pressure
of the compressed air in the tubes o has again sunk to that of the atmosphere, this
being obtained because a portion of the air escapes through the regulating device
described hereinafter.
Upon a train passing from left to right, that is, first over the left-hand pumping
arrangement in Fig. 2, then the lever u on the left in the apparatus showu in
Fig. 4, and having the insulated fork y, first operates, so that this fork catches the
lever v, this latter being then blocked, and prevented from coming into engagement
with the projection w, in consequence of which the circuit remains open.
Referring now to the modification illustrated in Figs. 5 tc 8, those parts
corresponding to those of the previously-described construction are desiguated by
the same reference letters.
In this second construction, only the apparatus shown in Fig. 6, on the right
hand, is provided with a pump (see also Fig. 8). The pressure pipe o of this
pump is carried into the box c of the apparatus shown on the left-hand of Fig. 6
(see also Fig. 7).
The air compressed by the pump operates again on the diaphragms, and its
pin t, which, when the apparatus shown in Fig. 8 is operated first by the train
presses the contact lever u against the contact plate, and thus closes the circuit

page_text: When the wheels of the train pass first over the apparatus shewn at Fig. 7, the
booked nosef of the unequally-armed lever f catches the nose of the lever u,
and holds it fast, so that the air pressure produced by the passage of the train over
the second apparatus (Fig. 8) cannot bring the lever u into contact with the
contact plate 2. The longer arm of the lever f, Fig. 7, is connected to the piston
of a dash-pot f, to allow the lever to return only slowly to its normal
position.
In
The apparatus shewn in Fig. 7, when modified as shewn in Fig. 9, will give
always signals, whether a train passes in one or the other direction. This modified
arrangement is principally adopted for use in checking the speed of trains.
this case, the longer arm of the lever fis pressed against the contact plate by the
Bagging of the rail, and after the train has passed over the apparatus, the lever f
falls slowly, under the influence of the dash pot f", back to its normal position.
To adapt the duration of the closure of the circuit to requirements, there is
provided on each diaphragm casing, or at any other other convenient place, a
device for regulating the escape of air. Said device may consist of a regulation
screw device, a valve arrangement, or the like. Such a regulating device is shewn
at Fig. 10 in side view, partly in section. This device consists of a screw a,
provided along its length with a thread, and a conical groove o, widening towards
the end of the screw (see Figs. 10 & 104). The screw carries a lock nut 6 for
the purpose of holding the screw in any determined position in the diaphragm
casing r. To facilitate the escape of air, the lock nut is coned out on its underside,
and has a notch d cut in it (see also Fig. 10B).
When the screw is screwed fully into the casing r, very little air can escape
through the groove c, and the duration of the contact will be proportionately
increased.
The unscrewing of the screw a, on the other hand, brings a wider part of the
groove c into position, and allows for a more rapid escape of the air from the
casing, and therefore an earlier breaking of the circuit.
All the devices herein described are placed conveniently to the auxiliary rails a
(see Figs. 1, 2, 5, and 6), which have their points of support on the railway-rail
a greater distance apart than has been hitherto customary, these points being
beyond two adjacent sleepers. In consequence of this arrangement, the "sagging
movement of the railway rails is better utilized than if each apparatus were fixed
on two adjacent sleepers, and, as a result, a sure and certain action of the apparatus
is secured, even with trains travelling at the highest speeds. The above described
"circuit closer" is connected by a single line wire with the arm-, disc-, and light-
signals, alarm bells, and the like, placed in convenient positions, so that the
particular signal is brought or communicated at the same instant to the desired
signalling position or point, as the train, or portion of a train, passes over the
particular contact maker. This apparatus is adapted as a security against
collisions on entering and leaving a station, and at crossings, tunnels, bridges, sharp
curves, heavy gradients, &c.
On block sections, the contact makers can be connected to the block signals in
such manner that the train, as it passes from block to block, signals its presence
ahead, simultaneously blocks the section or block over which it has just passed,
and also, at the same time, unblocks the train following it from block to block,
in such a way, that there is always one completely blocked section between two
trains, and the trains are thus allowed to follow each other in the closest possible
order, with the minimum amount of distance between each.
The contact maker may also operate alarm apparatus connected with a movable
or adjustable disc, in such manner, that, at a sufficient period of time before the
train passes a level-crossing, the alarm sounds, and the disc shews the signal
"Stop," whilst, when the train has passed the said crossing, the arm shews the
signal "Clear," and the alarm is silenced.
For the purpose of controlling the speed of travelling, the apparatus shewn in
Fig. 9 is provided with a registering device.

page_text: • 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. The means for giving signals on railway tracks, and consisting of two devices
or apparatus placed below one of the rails, a certain distance apart, each provided
with a vertically sliding bolt d, one end of which abuts against the foot of the
rail, and the other upon an unequally arined lever f, and operated by the sagging
of the rail, and in communication with contact devices or apparatus, in such
manner, that one apparatus, on the passage of a train in one direction, causes the
approach of the contact devices, whilst the other apparatus, on the passage of a
train in the opposite direction, prevents the said contact devices from coming
together, substantially as described.
2. In signalling apparatus for railways, the arrangement of two air-pumps
operated by the sagging of the rail, in combination with the diaphragms or other
distensible bodies, which close the pressure pipes of both pumps, and operate upon
a single signalling circuit, substantially as described.
3. In signalling apparatus for railways, a single air-pump in combination with
another device which has, upon its unequally armed lever, an engaging hook,
which, when a train passes in the reverse direction, prevents the first apparatus
acting upon a contact lover, substantially as described.
4. In signalling apparatus on railways, the arrangement of a frame supporting
one of the apparatus and lying parallel to the rails, the points of attachment being
a sufficient distance apart to allow of the "sagging" of the rail being utilised to its
utmost for operating the apparatus, substantially as described.
5. A signalling apparatus for railways having only one device operated by the
sagging of the rail, the said device having an unequally armed leverf operated
by the vertically moving bolt d, the longer arm of the lever acting upon a contact
plate 2, and being connected to a dash-pot, for gradually returning the lever f
to its original position, substantially as set forth.
6. In combination with the arrangements above described, a regulating device
by which the escape of the air compressed by the air pump into the apparatus
may be regulated, so that the duration of the closure of the circuit, and
consequently the duration of the operation of the current upon the signalling
apparatus, e.g., registering mechanism, moving disc- and light signals, acoustical
signals, and the like, may be adjusted, as desired, substantially as described.
Dated this 13th day of October 1896.
NEWTON & SON,
Agents for the Applicant.