IMPROVEMENTS IN RAILWAY SIGNALLING APPARATUS
Year: 1884

page_text: We, JOSEPH TOMLINSON, Junr, of 64 Priory Road, West Hampstead, in the
County of Middlesex, Engineer, and AUSTIN CHAMBERS of 214 Marylebone Road,
in the County of Middlesex, Engineer, do hereby declare the nature of said
invention for "IMPROVEMENTS IN RAILWAY SIGNALLING APPARATUS" to be as
follows:-
The object of this invention is to render it impossible for a railway signalman to
take off a signal without the concurrence or co-operation of a second person. This
second person may be a signalman at the station in advance, when the line is
worked upon the block system, or may be a station master or other official upon
whom the duty of allowing the signal to be taken off devolves.
The invention has reference to means for making and breaking the physical
connection between the signalman's lever and the semaphore arm or its equivalent;
so that the motion of the lever may have no effect upon the arm or its equivalent
which is normally "on" or at danger, unless the two be connected by the action of
a second person as above mentioned. This connection is effected by aid of an
electric current flowing in a circuit which can be completed and interrupted as
desired.
When the circuit is completed the current flows, and, through the intermediary
of an electro-magnet maintains the connection of the lever and arm or its equivalent.
When the circuit is broken the current ceases, the magnet loses its power and the
working connection ceases. The mechanism by which the physical connection and
disconnection is effected may be situated near the lever, or near the semaphore arm
or its equivalent or at any intermediate point between the two.
If it be placed near the semaphore arm or its equivalent it may be conveniently
arranged on the "pulling-off" rod connected to the arm or signalling device.
In such case this rod is made in two independent parts which for a portion of
their lengths are parallel to each other, and are each capable of endwise motion.
Each part is provided with a tooth, claw, stud or tappet, or one may be so provided
and the other have a recess. When the connexion aforementioned is made by the
second person in order that the arm may be depressed one of the teeth studs, claws
or tappets engages with the other, or with the recess, and thus the two parts of the
rod are temporarily united, so that the endwise motion of the one under tension, is
transmitted to the other-The engagement is effected as follows; The rod carries
D

page_text: between its end and the above mentioned tooth, claw, stud or tappet, a coil of
insulated wire forming part of the circuit under the control of the second person.
When this coil is traversed by a current polarity will be produced at the free
end of the rod, and at the tooth or claw. This free end stands opposite an
armature on the other part of the rod, and is normally drawn away from it by a
weight or spring, but it is provided with a guide by which it is forced towards the
armature in opposition to the weight or spring when it is raised.
Consequently the magnet pole and the armature are normally in or nearly in
contact, and the magnet has no actual motion to produce. If the signalman pulls
his lever when the current is flowing the pole slides over the armature until the
tooth or claw engages with the corresponding tooth or recess and then the two
move together. If the current be not flowing, the pole, being no longer held by
the armature moves backwards under the guide, by reason of the weight or spring
at the same time that it moves downward, and the tooth or claw misses the
corresponding tooth or claw or recess.
If the mechanism be situated near the operating lever it is essentially the same
as that described above, but modified to suit the altered position.
One of the parallel sliding rods is bent or cranked, and has an electro-magnet
mounted upon it exercising a direct attraction upon the other rod. The claws or
tappets, and the guide to keep the magnet normally against or near the armature
are as in the preceding example.
.
The current which excites the magnet may also operate a visual or audible signal
to inform the signalman and the current may be broken in more than one place so
that the concurrent action of two or more people may be necessary to effect the
physical connection.
Such apparatus may also be used in conjunction with or independently of
electrical signalling apparatus of various known or suitable kinds.
It will be evident that assuming a signal to be lowered either the person in
charge of it or the person at a distance will be able-with-this-apparatus_to_cause
the signal to assuine the danger attitude.
D1012
A: 100A

page_text: Wo, JOSEPH TOMLINSON Junior, of 64 Priory Road, West Hampstead, in the
County of Middlesex, Engineer, and AUSTIN CHAMBERS, of 214 Marylebone
Road, in the County of Middlesex, Engineer, do hereby declare the nature of said
invention for "IMPROVEMENTS IN RAILWAY SIGNALLING APPARATUS" 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 render it impossible for a railway signalman
to take off a signal without the concurrence or co-operation of a second person.
This second person may be a signalman at the station in advance, when the line is
worked upon the block system, or may be a stationmaster or other official, upon
whom the duty of allowing the signal to be taken off devolves.
The invention has reference to means for making and breaking the physical
connexion between the signalman's lever or levers and the semaphore arm or its
equivalent; so that the motion of the lever or levers may have no effect upon the
arm or its equivalent, which is normally "on" or at danger, unless the lever or
levers and semaphore arm or its equivalent be connected by the action of a second
person as above mentioned.
This connection is effected by aid of an electric current flowing in a circuit
which can be completed and interrupted as desired.
When the circuit is completed the current flows, and, through the intermediary
of an electro-magnet, maintains the connection of the lever or levers and semaphore
arm or its equivalent. When the circuit is broken the current ceases, the magnet
loses its power and the working connection ceases. The mechanism by which the
physical connection and disconnection is effected may be situated near the lever or
levers or near the semaphore arm or its equivalent or at any intermediate point
between the two.
If it be placed near the semaphore arm or its equivalent it may be conveniently
arranged on the "pulling-off" rod, connected to the arm or signalling device. In
such case this rod is made in two independent parts which for a portion of their
lengths are parallel to each other, and are each capable of endwise motion. Each
part is provided with a tooth, claw, stud, or tappet, or one may be so provided and
the other have a recess. When the connexion aforementioned is made by the
second person in order that the arm may be depressed one of the teeth, studs,
claws, or tappets engages with the other, or with the recess, and thus the two parts
of the rod are temporarily united, so that the endwise motion of the one is trans-
mitted to the other. The engagement is effected as follows; The rod carries
between its end and the above-mentioned tooth, claw, stud, or tappet, a coil or coils
of insulated wire forming part of the circuit under the control of the second
person.
When this coil or coils is traversed by a current the core of the cuil becomes
polarized. The free end in one arrangement stands opposite an armature on the
other part of the rod, and is normally drawn away from it by a weight or spring
bnt it is provided with a guide by which it is forced towards the armature in
opposition to the weight or spring when it is raised,-Consequently the magnet
pole and the armature are normally in or nearly in contact, and the magnet has
little actual motion to produce.
If the mechanism be situnted near the operating lever or levers it is essentially
the same as that described above, but modified to suit the altered position.

page_text: One of the parallel sliding rods is bent or cranked, and has an electro-magnet
or magnets mounted upon it exercising a direct attraction upon the other rod. The
teeth, claws, or tappets, and the guide to keep the magnet or magnets normally
against or near the armature are as in the preceding example.
The current which excites the magnet or magnets may also operate a visual or
audible signal for information of the signalman, and the current may be broken in
more than one place so that the concurrent action of two or more people may be
necessary to effect the physical connection.
Such apparatus may also be used in conjunction with or independently of
electrical signalling apparatus of various known or suitable kinds.
It will be evident that assuming a signal to be lowered either the person in
charge of it or the person at a distance will be able with this apparatus to cause
the signal to assume the danger attitude.
It will also be evident that two or more signals may by means of this invention
be controlled at one operation by a person operating a single controlling instrument,
-and that for this purpose all the signals may be in one circuit or the controlling
instrument may be a multiple contact maker and breaker.
Fig 1 sheet 1 of the accompanying drawings shews in elevation an ordinary
railway signal post, to which apparatus according to our invention is applied at A.
Fig 2 (sheet 2) shews at right angles to Fig 1 a detached view of such apparatus,
drawn to an enlarged scale; and Fig 3 is a view of the same at right angles to
Fig 2-a is the signal post carrying a semaphore arm b operated by a "pulling
off" rod constructed in two independent parts c, and d. e. e¹ aro guides for guiding
the part e during its endwise movement. The guides e. e' may be carried by a
bracket plate f. secured to the post a. The part of the rod carries a guide
piece e arranged to slide on part c; g is a coil; it is carried by an extension or
eore piece d', pivotted at d to the guide e, attached to part d of the rod. g¹, g' are
the terminals of the coil.. h and are respectively a recess in part c of the rod
and a tooth carried by diisa-spring-fixed_to_d. This spring tends to maintain
the extension or core-piece d¹ of the rod in the normal position shown-in-the-
drawing, wherein it is disengaged from c. j is a screwed bolt, passing through
part of the rod, and provided with a nut ¹ for regulating the action of the
spring. When part c of the rod is of magnetic material, such as iron or steel, its
projecting part c* constitutes an armature to the free-end or pole d of the
extension or core piece d¹. If the part c be not of magnetic material then a
suitable magnetic armature must be secured thereto at c* for the purpose of
attracting the pole piece d when the latter is magnetised. * is a curved guide
projecting from guide c,-its office is to force the pole piece d* towards the arma-
ture c* in opposition to the spring i when part d of the rod is raised. e* must be
of non-magnetic material.
In the modified arrangement of apparatus shown in Figs 4 and 5, which are
similar views to Figs 2 and 3 respectively, the extension or core piece d' is hinged
or pivotted to cheeks d secured to part d of the "pulling off" rod, which in this
arrangement is extended upward and is guided by the guides e, e'. c* is an
armature portion of part c of the rod whose office it is to attract the pole piece d*
of the electro magnet or coil g when the latter is traversed by a current. j, j are
set screws for limiting the lateral movement of the extension or core piece d
and h¹ are teeth or claws formed on the parts o and d' respectively If c be not
of magnetic material h must be of magnetic material as well as c* c* is the
curved guide for the purpose hereinbefore mentioned; it is shewn attached to the
part c of the rod, and must be of non-magnetic material.
The operation of the apparatus is as follows:-When the signalman pulls his
lever the part d of the "pulling off" rod is operated through the intermediary of a
chain (Fig 1) and weighted lever on the post a in the usual manner.
Assuming the circuit to be closed so that an electric current is traversing the
electro magnet or coil g, if now the lever be pulled the pole piece d* will slide over
the armature c* until the tooth or claw engages with the shoulder or tooth at h

page_text: whereupon the two parts c and d will move together. If however the current be
not flowing when the lever is pulled the pole piece d* not being attracted by the
armature will be caused during its descent to move backward under the guide e*
by the action of spring i, and the tooth or claw h¹ will clear the corresponding
shoulder or tooth h of part c of the rod.
Figs 6 and 7 represent a modified arrangement of the apparatus adapted for use
near the operating lever or levers or between the same and the signal post. In
this arrangement c and d are the two parts that correspond to the "pulling-off"
rod in the other arrangements, and through which the necessary motion for
operating the signal must be transmitted. d is the cranked or bent portion of
part d' of the rod; it is pivotted to and carried by a frame m. n is a rod worked
by the signalman for operating the signal through the frame m, parts c and d, and
chain, or other connection, k. g is the electromagnet or coil (as before) carried by
the bent portion d' of part d of the rod; and d* is one pole of the magnet which
when magnetised is held by attraction to part c. hh are the teeth on the parts c
and d respectively, and e* is the guide for forcing the pole piece d* towards the
adjacent portion of the part c that acts as armature. o is a spring connected at
one end to the frame m at m¹ and at its other end to part d of the rod as shown;
This spring tends to withdraw d from c. e is a guide for part c. The frame
moves along and is guided by part c. p is a sheave or wheel for changing the
direction of the chain or other connection k. The action of this modified arrange-
ment is similar to that of the other arrangements and will be readily understood
without further description.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is
1. In railway signalling apparatus of the kind referred to above the use in
connection with a semaphore arm or its equivalent and an operating lever or lovers
of a divided rod with teeth or other engaging devices, an electro-magnet carried
by or attached to one part of such rod, an arinature carried by or attached to the
other part, a guide (such as 6*) which as the signal is raised moves the engaging
devices into and keeps them in position for connecting the separate parts of the
rod, and a spring or weight that tends normally to disconnect the separate parts of
the rod, the arrangement being such that if the lever or levers be actuated to
lower the semaphore arm or its equivalent whilst the circuit is closed the separate
parts of the rod will by the action of the electro-magnet be held in connection so
that the semaphore arm or its equivalent may whilst the circuit is closed be
lowered or moved into the safety attitude, but should the circuit be broken the
semaphore arm or its equivalent will immediately assume the danger attitude and
will retain that attitude notwithstanding any movement of the operating lever or
levers so long as the circuit remains broken, substantially as described.
2. The construction and arrangement of railway signalling apparatus substantially
as hereinabove described with reference respectively to Figs 1, 2 and 3, Figs 4
and 5 and Figs 6 and 7 of the drawings.