Improvements in and relating to Railway Signals.
Year: 1889

page_text: Date of Application, 12th Aug., 1889-Accepted, 14th June, 1890
COMPLETE SPECIFICATION.
Communicated from abroad by WILLIAM FRANCIS ZENT DESANT, of the Hotel
Metropole, in the City and State of New York, United States of America,
Electrician.]
Improvements in and relating to Railway Signals.
I, HENRY HARRIS LAKE of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings in the County of Middlesex, 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 improvements in block signals and other railway signals,
and its object is :-
To provide an automatic signal located in the cab of the engineer and so arranged
as to automatically indicate danger in the event that a train preceding has not passed
off the section in advance.
These objects are accomplished by the mechanism described in the accompanying
specification and illustrated in the drawings, but particularly pointed out in the claims
which follow.
Prior to this invention it was old in the art to so arrange a system of electrical
block signals that the presence of a train on a preceding section of track was
indicated to the engineer on a succeeding train by the ringing of an electrical bell in
the cab, but in the system of signals referred to the generator was carried in the cab
of the locomotive, while in the construction herein shown and described, the batteries
or generators are permanently located at the respective ends of the sections of track
as will be disclosed.
Referring to the drawings, Figure 1 is a plan view showing a block signalling
systein with two locomotives on succeeding sections of track, and main and local
batteries at the end of each block.
Figure 2 is a side elevation of a modified form of this block system applicable to
one set of rails the one set not shown being electrically continuous, shunts the
current from the magnet M through the axles of the tender and locomotive.
Figure 2 is a detail view of the whistle and detent releasing apparatus designed
to give the alarm or signal.
Figure 3 is a plan view showing the circuits applicable to a switch or drawbridge.
Figure 4 is a plan view showing the circuits at the way station with means for
announcing to the engineer on a train that he should stop, and additional means for
announcing the approach of the train.
Figure 5 is a detail view of one of the switching magnets which operate the block
circuits. R, R, Rare the rails divided into main sections 1, 2 and 3 as shown in
Figures 1 and 2. Land are two locomotives running on successive block
sections; at the end of each block there is a short section of rail F F F shown in
Figure 2, electrically insulated at each end from the adjoining rails. In Figure 1
there are two such short sections of rails between each block section to meet the
Each of the switch
requirements of the modified form therein shown.
magnets M, MI, M³ is provided with an armature lever A, A1, A2 having an armature
Don each end and pivoted as shown so that it may be tilted in either direction. On
the end of these armature levers are insulating blocks I, I 12.
B, B, B are the batteries for operating the switch magnets M, M', M³ as will be
described. w, we are the block signal circuits, and w¹, w' are the alarm circuits seen
in Figure 1 and Figure 2.
8, s, ² are metallic springs adapted to bear on either the metallic or insulated faces
of the armature levers A. A¹ or A³. w³ to³ is a local circuit running from the axle of

page_text: the rear locomotive drive wheel to the magnet M' in the cab and thence to the axle
of the cab truck, the function of which circuit is to energize the magnet M³.
RR Figure 3, are switch rails having the usual switch lever s 10,
which is
provided with a contact arm adapted to close the circuit of the battery B' including
the circuit wires w, w.
H Figure 4 is a band switch located in a way station and adapted to close the
circuit of the battery B, and the wires w², to at the proper time as will be
described.
D is an alarm bell operated by the battery B², in a local circuit including the
armature lever A*, of magnet M', when the train approaches the station.
The description of the operation of the modified form in Figure 1 will now be
made.
Suppose the engines L, L' to be in the middle of the sections 2 and 3, as shown.
When the engine L reaches the point a', there will be no alarm in the cab, for the
reason that the battery B' will be short circuited through the axles of the locomotive
drive wheel and tender truck, wires w', spring S and armature lever A. This will
indicate to the engineer that the section in advance is clear. If in the meantime
engine L reaches the point A³, the circuit of battery B' will be closed as
follows.
From the copper pole through the axle of the locomotive drive wheel, wire to³,
magnet M³, wire to³, tender truck wheel and axle back to the negative pole of the
battery, the short circuit ww being broken by the insulation I, between the
armature lever and spring S¹. This energizes magnet M³ Figure 2, and causes its
armature A³ to release the weighted lever c, which in turn through the agency of
the link W and valve V, permits the whistle W² to be blown.
When the engine I advances to the point a, the main circuit of battery B at
station I is closed as follows.
Through the wheel of the locomotive between the wires w, w, the lower half of
magnet M, and to the succeeding section 2, through the upper half of magnet M.
This causes the armature levers A and A¹ to be tilted to the right and left
respectively, thereby placing the circuits in such conditions as to indicate to the
engineer of locomotive L', that locomotive L has passed out of block 2, and at the
same time leaving the local circuit of battery B' at station 1 in condition to sound
an alarm on the locomotive L', when it reaches that point if locomotive L has not
passed out of section 1 in the meantime. When locomotive L' passes point a² the
armature levers A' and A', are tilted to the left and right respectively, setting A2 at
safety, and A' at danger.
•
Referring to Figure 2 the second set of rails, not shown, is made to break joints
with the rails F FF, so that there shall be breaks between the said second set of
rails directly opposite the points a¹, a³ and a and that the said rails shall be
electrically continuous opposite the points a, a² and a so that when the locomotive
crosses the points a, a, a the circuit from battery B will pass by wire w, through
the rear driving wheels of the locomotive and their axle to the opposite rail, thence
through the said opposite rail to the forward driving wheels and their axle, back
again to the rail F, and by wire w to the distant magnet M' or M' thereby 4
manipulating the armatures A¹ or A as the locomotive passes out of the respective
blocks.
The alarm controlled by the magnet M³ on the engine will be operated whenever
the armature levers are in the position shown at A' and A2 and when the locomotive
and tender are located as shown in the right hand position at station 2, so that the 5
current from battery B* will pass through the armature A' spring S¹, wire w¹,
rail F, wire w³, magnet M³ wire to to the tender through the truck wheels of the
tender to the rail R by wire w' back again to the battery.
The alarm will not be sounded however, when the locomotive assumes a similar
position over the breaks a, a² and a because of the low resistance path which is 5
offered to the current from the batteries B by way of the tender and truck wheels, their
axles, to the distant rail, and back again through the locomotive driving wheels to

page_text: the near rail, the said path being of much lower resistance than that offered to the
current from the truck wheels, wire w' magnet M and locomotive wheels.
In other words, the breaks in the opposite set of rails at the points opposite the
breaks a', a and a³ leave only one path for the current through the alarm magnet M'
when the locomotive and tender assume the position shown at station 2, over the
break a, while the low resistance path through the truck wheels and locomotive wheels
to the opposite rail will prevent the battery B from sounding the alarm over the
breaks aa, a and will at the same time permit said battery to energize the
magnets M M M² as the locomotive advances.
When the armatures A, A', A', are in the position of safety, as shown in Figure 1 at A,
at station I, the incoming locomotive L, will pass over the insulated joints a', and when
the last driving wheel of the locomotive and the first wheel of the tender are in such a
position as to straddle the break a', the current from the battery B' will take the low
resistance path through the wire ', armature lever A, spring s, wire w', through the
axles of the tender wheel to the other rail back again to starting point to the axles of
the locomotive wheel.
It is true at this same time the circuit is closed through the signalling magnet M³,
but the first named path being of so much lower resistance no signal will be sounded.
On the other hand, when the apparatus is attached to the single set of rails shown,
as in figure 2, then the battery current will pass through the signalling magnet M³,
and actuate it every time the locomotive and tender bridge the space a¹, a³, or a
provided the armature levers a, a', a², are in the position shown for the magnets M¹
and M. There will be no signal however on this modified form when the armature
is in the position shown at station because the insulating block on the armature A is
under the spring s.
It is the function of the batteries B' B¹, figure 1 to operate the alarm in the cab
exclusively and that of the batteries B to operate the signal switch magnets. Of
course it is to be understood that the locomotive and tender are insulated from each
other and that the only electrical connection between the truck wheels and the rear drive
wheels is through the conductor 10³, 103.
In figure 2 the engine on section 1 has passed out of that section so that the armature
lever A of magnet M is at safety; while armatures A1 and A2 are in the reverse positions,
the engines Land L' not having yet passed out of their respective sections 2 and 3.
When engine L passes over the space a no circuit will be made from local
battery B Fig. 2 through the maguet M³ on the cab and hence no alarm will be
sounded showing safety on section 1. As the armature A' is in reverse position, it
will be seen that the local circuit from battery B will be closed through this arinature
lever by spring s¹, and wire w' locomotive wheel wire w³, magnet M³, wire to³, tender
wheel and wire w', thus sounding an alarm as shown. Similarly the next succeeding
engine (not shown) would receive an alarm on entering section 3.
As engine L passes out of section 2 into section 1, it closes the circuit of battery B
through drive wheel, wires we, w, lower half of magnet M, and upper half of magnet M',
thus reversing the switches or armature levers A and A', and placing them to indicate
safety to an in-coming train to section 2 and danger for section 1. Similarly engine L'
will set switch armature A to safety and A' to danger as it passes out of section 3 and
into section 2.
The operation of the switch and drawbridge circuits Figure 3 will be understood in
view of what has already been said concerning the blocking circuits; it being under-
stood that the alarm circuit is closd through the cab as before, at the point a. When
it is desired to stop the train at a way station the station master closes the circuit of
the hand switch H, Figure 4, and the alarm is sounded in the cab as before, the
approach of the train having first been announced by the action of the lower half of
the magnet M, on the armature lever A', causing it to tilt to the right and close the
local circuit of battery B², thereby ringing bell D. As the train arrives at the station
5 the circuit of battery B is closed through the upper half of magnet M' at the point a°,
thereby causing the armature lever A to tilt into the position shown so that the bell
stops ringing.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me
by my foreign correspondent I declare that what I claim is :-
First In a system of block signals for railways, the combination of a main battery
located at one end of a block section in a circuit including one coil of a switching
magnet at the home station and one coil of an additional switching magnet at a distant
station, with a local battery also located at the home station having circuit connections
as described, with the armature lover of the switching magnet and a local circuit
extending into the cab of the engine, including a magnet the armature of which
controls an alarm, substantially as described..
:
Second In a system of block signals for railways, the combination of a series of
batteries one for each block section, each of which includes in its circuit one coil of a
switching magnet at the home station and the additional coil of a switching magnet
at the next station in the rear, with a local battery at each station and circuit con-
nections as described for closing a circuit through an alarm apparatus in the cab of
the engine, substantially as described.
Third: In a system of block signals the combination of the following elements ;-
A main or switching battery and a magnet at each block having two independent
coils, switching circuits running to the joining advance and rear blocks and including
the separate coils of said magnets a local battery at each block including in its
circuit, the armature of the switching magnet the insulated ends of two adjoining
rails and an alarm circuit on the cab, substantially as described.
:
Fourth In a system of block signals for railways the combination of the following
elements; one main or switching battery for each block included in a circuit running
to one coil of each of two switching magnets, one of said magnets being near the
battery and the other at the next block to the rear; a local battery at each block
including in its circuit the armature of the switching magnet, a circuit running, to the
insulated ends of two adjoining rails a signalling magnet located on the engine and
included in a local circuit, substantially as described.
Fifth In a system of block signals, the combination of two batteries located
at each block, one of which includes circuits and switching magnets located
at the home and rear ends of the block for manipulating the circuit relations of an
alarm located on the engine, while the second includes in its circuit the armature of
the switching magnet, the adjoining ends of two insulated rails of the track an alarm
magnet located on the engine and included in a local circuit substantially as
described.
Sixth In a system of block signals for railways, the combination of two circuits
for each block connected to a single line of insulated rails, one of said circuits
including a battery and one portion of the coils or two switching magnets located at
each end of the block, while the other includes a second battery the armature lever of
the first named magnet, the adjoining ends of two insulated rails an alarm magnet
located on the engine, and included in a local circuit, substantially as described.
Seventh-In a system of block signals for railways, the combination of the following
elements-A single line of rails separated into block sections by insulation; a single
battery for each section including in its circuit the insulated ends of the rails and one
coil of a magnet at the battery end of the block and one coil of an additional magnet
at the distant end of the block ; a tilting armature lever for each magnet adapted to
tilt to the right or left according to which half of the magnet is energized; a local
circuit including each tilting armature lever and a separate battery with circuit con-
nections as described running to the insulated ends of two adjoining rails and a circuit
on the engine including an alarm magnet whereby the engineer is warned in the
event of danger in advance, substantially as described.
Dated this 12th day of August 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.