Improvements in or relating to Railway Signalling or the like.
Year: 1894

page_text: Date of Application, 18th June, 1894
Complete Specification Left, 18th Mar., 1895-Accepted, 15th June, 1895
PROVISIONAL SPECIFICATION.
Improvements in or relating to Railway Signalling or the like.
We, WILFRID SWANWICK BOULT of 60 Castle Street, Liverpool, in the
County of Lancaster, Electrical Engineer, and CEDRIC RANDAL BOULT of
62 Dale Street, Liverpool aforesaid, Merchant, do hereby declare the nature of
this invention to be as follows:-
This invention relates to improvements in the system and means set forth in our
former Specification No. 17041 of 1893 wherein we describe the arrangement at
different places along the railway track of one or more permanent or electro-
magnets, capable, under the control of a signalman of being moved into or out of
operative position or magnetised or de-magnetised, and upon the locomotive or
other part of the train a divided armature or two armature bars with a gap between
them, in which latter a tongue or plate, is caused, by the magnetism, to operate so
as to effect the sounding of an audible signal or the closing of an electric circuit for
actuating any desired signalling device; or the reverse of this arrangement
according to said Specification may also be provided, that is to say the magnet or
magnets on the locomotive or train, and the armature-bars on the track.
According to our present invention we may arrange the magnets so that their
polarity may be reversed thereby admitting of the giving of two distinct signals for
example "danger" and "line clear." This, in the case of permanent magnets, may
be effected by reversing them so that say the N poles may occupy the position
before occupied by the S poles or by having one or more pairs of permanent
magnets mounted on a rocking shaft so that the N and S poles of one magnet of
each pair may be moved over into the positions before respectively occupied by the
S and N poles of the other magnet of the pair.
In the case of electro-magnets the reversal' of polarity is effected by reversing
the exciting current as for example by an ordinary reversing switch, by using
different coils or otherwise.
The contact maker may be arranged in the gap between the armature bars and
consist of a pivotted polarised contact bar or needle, two terminals and a magnetised
controller, this device being so arranged that' when the poles of the réversible
magnets are say the south at the right, and the north' at the left the contact
bar will be moved against one terminal and cause the electric current to flow in one
circuit and when the south pole is at the left and the north at the right the contact
bar will be moved against the second terminal and cause the electric current to flow
in another circuit.. When no magnetic field exists the contact bar is held in its
central position by the before mentioned magnetised controller.
By employing a polarised rocking bar for operating the necessary contacts, and
magnets, which, at the same time, present similar poles to the two ends of the
rocking bar, said bar may be caused 'to move in one direction or the other according
to whether the magnetic poles presented to it are of N or S polarity; or the same
result may be obtained by employing a rocking bar composed of two permanent
magnets connected end to end, similar poles together and operating on this by a
permanent or electro-magnet of reversible polarity as before described.
A convenient way of applying our invention to the automatic actuation of roadside
siguals or semaphores may be as follows;—this example embodying three different
semaphores which.for convenience we herein refer to as 1, 2 and 3 located at the
1, 2 and 3 signal stations respectively.

page_text: The circuit closer may be placed on the ground and the field magnets on the
locomotive in which case as the field never has to be destroyed or reversed fixed
permanent magnets will answer the purpose.
The semaphores are each weighted to fly to "danger" and pulled by an electric
coil or solenoid to "line clear "the solenoid core being connected to the semaphore
in any convenient manner. The three coils or solenoids are all connected in series
in an electric circuit extending along the railway.
In the same circuit, conveniently connected in the return wire, are three electro-
magnets one at each signal station and each wound with two equal coils in series in
opposite directions, so that, when the current flows through both, magnetic induction
is neutralized. Connected to the point of junction of the two coils of each magnet
is a wire, leading to the oscillating tongue or plate in the divided armature of the
next signal station, thus the point of junction of the two oppositely wound coils at
No. 1 signal station is connected with the oscillating tongue at the No. 2 signal
station and the similar point of junction of the No. 2 signal station is connected
with the oscillating tongue at the No. 3 signal station and so on throughout the
series. On each oscillating plate may be mounted an insulated spring-controlled
catch normally supporting a contact or switch bar which when released short
circuits the solenoid at the same station, and the catch may carry an insulated plate
or tongue in electric connection with the wire from the electro-magnet at the
previous station, such plate or tongue being so placed that when the oscillating
tongue in the armature is pulled over by the passing magnets on the train it
completes the path between the return wire and the junction of the two coils on
the electro-magnet and so short-circuit one coil and allows the other to energise the
magnet.
66
Suppose now a train to have passed signal 2 which has thereby been raised to
danger" and to be travelling towards signal 3 which is off or at "line clear," being
retained in that position by the passage of the current through the No. 3 solenoid,
the operation is as follows:-
As the engine's magnets pass over the divided armature at No. 3 signal station
the movable tongue is deflected and the catch releases the short-circuiting switch to
cut the No. 3 solenoid out of action, the No. 3 semaphore being thereby free, under
the influence of its counter-weight to move to its "danger" position. At the same
time the contact plate carried by the catch comes against a contact and momentarily
short circuits one of the oppositely wound coils at the No. 2 signal station so that
the other of these coils energizes the magnet which lifts the contact bar till it is
caught by its spring catch again throwing the No. 2 solenoid into action and
drawing No. 2 semaphore to its "line clear" position.
Any desired number of signal stations may be included in the same circuit.
The before described apparatus may be modified without departing from the
spirit of the invention.
Deted his 10th day of Tu 100
:
Improvements in or relating to Railway Signalling or the like.
We, WILFRID SWANWICK BOULT, of 60 Castle Street, Liverpool in the
County of Lancaster; Electrical Engineer, and CEDRIC RANDAL BOULT, of
62 Dale Street, Liverpool, aforesaid, Merchant, 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 the system and means set forth in our

page_text: former Specification No. 17041 of 1893 wherein we describe the arrangement at
different places along the railway track of one or more permanent or electro-magnets,
capable, under the control of a signalman, of being moved into or out of operative
position or magnetised or de-magnetised, and upon the locomotive, or other part of
the train, a divided armature or two armature bars with a gap between them, in
which last a tongue or plate is caused by the magnetism to operate so as to effect
the sounding of an audible signal, the closing of an electric circuit for actuating any
desired signalling or controlling device, or the operation of any desired apparatus.
Or the reverse of this arrangement according to the said Specification may also be
provided; that is to say the magnet or magnets on the locomotive or traiu, and the
armature bars on the track.
According to our present invention we may provide means whereby the polarity
of the magnetic field is reversible thus permitting of the obtainment of two distinct
signals; for example, "danger" and "line clear." This, in the case of permanent
magnets, may be effected by reversing them so that say the N poles may occupy
the position before occupied by the S poles, or by having one or more pairs of
permanent magnets mounted on a rocking shaft so that the N and S poles of one
magnet of each pair may be moved over into the positions before respectively
occupied by the S and N poles of the other magnet of the pair. In the case of
electro-magnets the reversal of polarity is effected by reversing the exciting current,
as for example by an ordinary reversing-switch, or by using different coils, or
otherwise.
When no
A contact-maker may be arranged in the gap between the armature bars and
consist of a pivoted polarised steel bar or needle (or several such bars on one axis),
two or more terminals or contact plates, and a magnetic or other controller, this
apparatus being so arranged that when the poles of the reversible magnets are say
the S at the right and the N at the left, a contact-piece (formed of or moved by the
steel bar) will be moved against one terminal (or one pair of terminals) to perinit
the electric current to flow in one circuit, and when the S pole is at the left and the.
Nat the right the polarised bar or its equivalent will be moved in the reverse
direction and cause the electric current to flow in another circuit.
magnetic field exists the needle is held in its central position by the before
mentioned controller. (Instead of one bar capable of two separate movements from
the normal position, we may employ two needles of opposite polarity each of which
is permitted to move or produce the desired effect when moved in one direction
only.) As a safeguard against failure of action, two or more independent contact-
makers may be placed in the same armature-gap and an equal number of sets of
signal indicators may be used, so connected up that the signal would be given unless
all the contact makers or all the signal indicators or batteries failed at the same
time. By employing a polarised rocking-bar for operating or making the necessary
contacts, and magnets which at the same time present "like" poles to the two ends
of the rocking-bar, the said bar may be caused to move in one direction or the other
according to whether the magnetic poles presented to it are of N or S polarity; or
the same result may be obtained by employing a rocking-bar composed of two
permanent magnets connected end to end, similar poles together, and operating on
this by a horse-shoe permanent or electro-magnet of reversible polarity as before-
described.
In the accompanying drawings;-—
Fig. 1.is a cross section showing one arrangement of reversible track magnets
constructed and operating according to our invention.
Figure 2 is,a perspective view of another arrangement of reversible magnets.
Figure 3 shows a polarised rocking-bar brought on a vehicle over two track-
magnets presenting similar poles to its opposite ends.
Figure 4.is.a plan of the divided armature with a polarised contact-maker in the
gap thereof, and
Figure 5 is a cross-section through the gap in the armature, showing therein
another construction of polarised needle, with horizontal shaft.

page_text: Figure 6 is a sectional plan of the same.
Like letters indicate like parts throughout the drawings.
In the arrangement illustrated in Figure 1 a compound magnet is formed by the
two. vertical magnets NS and S N and the soft iron connecting yoke A. The
magnets NS and S N are mounted at the middle on two rocking-shafts B
(preferably not of iron) which rest in plummer-blocks C shown in dotted lines and
supported on the sleepers D. The shafts B carry the gear-wheels E both of which
are in gear with the larger wheel F. The wheels F and E may be so proportioned
that a small angular movement. of F say through 60° or such movement as may be
readily effected by a rod or wire attached near the circumference say at G will
rotate the shafts B through 180° and thus reverse the position of the vertical
magnets and therefore the polarity of the field between them; the reversal of the
polarity of the field of these magnets will result in reversal of the magnetic flux in
the divided armature or other device carried through the field in the manner
described in our before-mentioned prior Patent, and by thus varying the flux a
variation of signal may be produced in a manner well understood through the
intervention of a suitably mounted polarised needle or tongue.
In the construction shown in Figure 2 simple bent. horse-shoe magnets S N, NS,
are used, arranged in pairs, on arms H secured to a shaft B journalled in bearings
in convenient proximity to the track, the two magnets of each pair having their
similar poles together so that when rocked over on the shaft B the magnets in the
vertical (acting) position may as desired be those which give a field of N S or
of SN polarity. By setting the magnets with either series vertical, results are
obtained which are similar to those described with reference to Figure 1. G is the
point of connection for the signal wire or rod.
A counterbalance to the weight of the magnets and arms H may be carried by an
arm projecting downwards from the shaft B.
In Figure 3, NS and SN are the magnets carried on shafts B supported in
bearings on the sleepers or otherwise. bb are tail-pieces to which the link I is
coupled. Jis a counterbalance weight. The signal wire g may be attached at
either of the points GG, a weight or spring being employed to throw over the
magnets into the position shown when the pull of the wire is released.
The rocking bar on the train is shown at K pivotted at L in a casting / attached
to the underside of the engine or one of the vehicles its polarity being indicated
by the letters sn. It is shown tilted into the position it would assume when passing
over the N poles of the track magnets, the arm P making contact in the
mercury cups Q or equivalent contacts, the arm M being lifted further away from
the opposite contacts as the arm P descends. The contacts Q and O are shown
out of their real position for the sake of clearness; they would preferably be
enclosed in the casting 1.
RR are control springs which when not overpowered by the track magnets
maintain the rocking-bar K in its normal horizontal position not in connection with
either of the contacts Q and O. Either of the two similar magnets NS or SN
would alone actuate the rocking-bar K.
When by the operation of the signal wire g the shafts B of Figure 3 are turned
so that the S poles of the magnets N S take the places in which the N poles are
shown, the bar K when next passed through the field would thereby be given an
inclination opposite to that shown in the drawing, so that contact between the
arm M and cups O would be made, instead of between the arm P and cups Q.
The circuit through M and O is separate or otherwise different from that through
P and Q so that the signal obtained when one of these circuits is completed is
different from that obtained when the other is completed.
In Figure 4 T are the two armature bars or parts of the divided armature with
elongated pole pieces tt at their ends the whole being carried by a brass casting U.
is the polarised contact-maker, pivotted at its centre to the casting; V W are
the two terminals of the respective signalling circuits, and X is a controlling magnet
for holding the contact-maker ns normally clear of the terminals V. W when the

page_text: armature T is not magnetised. In this case the signalling circuit from V or W is
completed through the pivot of the polarised contact-maker in accordance with the
direction in which the contact-maker n is drawn.
In the modification illustrated in Figures 5 and 6 ns are a set of small magnets
carried by a shaft Y (preferably not of iron) pivotted in a frame as shown; these
magnets together form the contact-making magnetic device. T¹ is the end of one
bar of the travelling armature of which T is the continuation and t an elongated
pole-piece X is the controlling magnet.
The shaft Y at one end carries a
cross-bar Z for making the necessary contacts across either pair of the terminals or
tongues c carried on the insulating block i.
£
Although in the foregoing description we have spoken of the polarised needle or
equivalent device as a contact-maker" it must be understood that we do not
restrict its use to the closing of electric circuits, but that, as in the case of the
striking tongue" in our Patent No. 17041 of 1893 above referred to, it may be
applied to the doing of such mechanical work as striking a beil or percussion cap,
or pulling a trigger, or to other suitable purpose.
65
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is;-
1. In railway signalling apparatus reversing the polarity of a magnetic field for
the purpose described.
2. In railway signalling apparatus reversing the polarity of a magnetic field in
apparatus whereof a part is stationary on the road and a co-operating part is
transportable upon the rolling stock substantially as and for the purpose described.
3. In railway signalling apparatus whereof a part is stationary on the road and
a co-operating part is transportable upon the rolling stock permanent magnets so
constructed and arranged that the polarity of the operative magnetic field is readily
reversible substantially as and for the purpose described.
4. In railway signalling apparatus a polarised rocking contact maker or equivalent
substantially as and for the purpose described.
5. In railway signalling apparatus of the kind claimed in the second claiming
clause a contact-making device constituted by the combination with a polarised
rocking-bar or needle of terminals or contacts for separate electric circuits and
circuit closing devices in operative connection with the polarised rocking-bar or
needle with or without magnetic or other control devices for normally maintaining
that bar or needle in a neutral position substantially as and for the purpose
described.
6. In railway signalling apparatus the combination of interchangeable or reversing
magnets divided armature and polarised needle or contact-maker or equivalent
substantially as and for the purpose described.
7. In railway signalling apparatus the employment in combination with one or
more indicators of one or more contact making devices of the kind claimed in the
fourth claiming clause for the purpose described.
8. In railway signalling apparatus the combination with a contact-making device
of the kind claimed in the fourth claiming clause of magnets arranged so that their
like poles can be simultaneously presented to the opposite ends of the polarised bar
or needle substantially as and for the purposes described.
9. Railway signalling apparatus constructed arranged and operating substantially
as and for the purpose described and illustrated in Figure 1 or Figure 2 or Figure 3
or Figure 4 or Figures 5 and 6 of the accompanying drawings.
Dated his 10th 1.
1005
W. S. BOULT.
C. R. BOULT.