Electrical Fog Signalling Apparatus for Railways.
Year: 1896

page_text: Date of Application, 29th Apr., 1896
Complete Specification Left, 28th Aug., 1896-Accepted, 10th Oct., 1896
PROVISIONAL SPECIFICATION.
Electrical Fog Signalling Apparatus for Railways.
We, HERBERT TOMLINS of 100, Hammersmith Road, London, Decorator, and
CHARLES RIOHARD GURR of 30, Cranbrook Road, Chiswick, Builder, do hereby
declare the nature of this invention to be as follows:-
This invention relates to electrically controlled detonating or fog signal apparatus
for railways, the setting of the apparatus in position to cause the explosion of the
signal on the passage of the train, being effected by an electric current from a signal
cabin.
The apparatus comprises a cylinder or disc revolving on a horizontal axis and
carrying a series of explosion chambers or barrels each preferably provided with its
own firing pin and adapted to be brought in succession into position for said firing
pin to be acted on by a finger or striker for the purpose of exploding a cartridge.
The revolution of the cylinder step by step is effected by a weight or spring which
has been raised, or put into condition to act, by the depression by a previous train of a
treadle lever alongside the rail, the weight or spring being retained in readiness to
act by means of a self-engaging detent from which it can only be released by the
closing in the signal cabin of the circuit through an electro-magnet applied to act
on the detent mechanism. The weight or spring when thus permitted to operate
acts on the cylinder through ratchet and pawl or equivalent gear, and under the
control of spring detent or jumper mechanism, whereby the cylinder is turned the
limited distance necessary to bring the next barrel into firing position; the weight
or spring simultaneously raising the treadle lever into position to be depressed by the
wheels of the next train, the treadle lever when thus raised being supported by spring
detents which oppose sufficient resistance to prevent the accidental depression of the
lever but yield under the wheels of the train. The action of the weight or spring
besides turning the cylinder and raising the treadle, also brings a finger moving with
the latter into position, when the treadle is depressed, to act on and suddenly release
the spring of the firing hammer in order to explode the cartridge contained in the
barrel which was brought by the previous action of the weight or spring into firing
position. It is preferred to mount the revolving cylinder loose upon the shaft of
the treadle lever and to operate it by a weighted arm participating in the angular
motion of said shaft.
In order to concentrate the sound of the explosion in the required direction each
barrel when in firing position coincides with a stationary trumpet mouth.
In order to inform the signalman of the proper setting of the apparatus in position
to act and of the number of cartridges remaining unexploded, an electric tell-tale or
register is provided in the cabin which is actuated by the closing of the return circuit
by a circuit closer operated by the fall of the weight or the turning of the cylinder
whereby an electro-magnet moves a counter one step forward so that it exhibits a
number denoting how many cartridges have been, or remain to be, fired and an index
shewing whether the fog signalling mechanism is, or is not, set for action.
Provision is made for rendering the firing mechanism inoperative during the
operation of recharging the cylinder with fresh cartridges.
In order to render the operation of the cylinder as easy as possible its axis is
mounted in ball bearings and the cylinder and attached mechanism would be housed
in a casing to which the trumpet mouth is attached, and may be warmed during
frost by a lamp.

page_text: Any number of such fog signalling apparatus may be controlled from one cabin for
the various requirements of signalling and an electric gong would be provided for
restarting a train which has been stopped.
Dated this 29th day of April 1896
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
Electrical Fog Signalling Apparatus for Railways.
We, HERBERT TOMLINS of 100, Hammersmith Road, London, Decorator, and
CHARLES RICHARD GURR of 30, Cranbrook Road, Chiswick, Builder, 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 electrically controlled explosive signalling apparatus for
use on railways in foggy weather, or when the road is under repair, or the ordinary
visual signals are out of order, the setting of the apparatus in position to effect the
explosion of the signal on the passage of the train being effected from a distance
preferably through the medium of an electric current.
The invention will be described with reference to the accompanying drawings
forming part of this Specification wherein
Figure 1 is an elevation (the casing being in section) of the wheel-operated treadle
lever for exploding the cartridge and also putting the firing apparatus in condition
to be reset for another train.
Figure 2 is an elevation (the casing and treadle-operated shaft being in section) of
the mechanism for rotating the cartridge-carrying disc so as to bring a cartridge into
firing position.
Figure 3 is an elevation (viewed in the opposite direction to Figure 2) part of the
casing being broken away to shew the cartridge carrying disc and firing mechanism.
Figure 4 is a side elevation of the entire apparatus.
Figure 5 is a detail sectional view of the breech and firing mechanism of a cartridge
chamber.
Figure 6 is a front elevation (the casing in section) of a tell-tale instrument in
the signal cabin to indicate the position of the apparatus and shew the number of
cartridges fired..
Figure 7 is a detail.
The same letters of reference denote like parts in all the figures.
which
A is a treadle lever alongside the rail which when raised as shown is in position to
be depressed by the wheel, the part A' struck by the wheel flange being formed by a
curved spring rising above the rail level so as to avoid shock and ensure the sufficient
motion of the treadle under all circumstances. This treadle is fast on a shaft B
passing beneath the rail and having fixed upon it the disc-revolving lever
acts either by the gravity of its weighted arm C' or by a spring attached thereto.
D is a cartridge-carrying disc turning loose on shaft B and having ratchet teeth with
which engages a pawl e pivoted at c' to the lever U, the pawl being pressed into
engagement by a spring applied in such diagonal position as to brace the pawl and
60.relieve the pine from racking strain in carrying round the disc D. The disc is
turned to the extent of ona tooth by each fall of the weight C' which rotates the disc
and also raises the treadle A to operative position whenever said lever is permitted to
come into action by the signalman under whose control it is placed. This disc D has
as many cartridge chambers or barrels E as there are ratchet teeth, the chambers or
barrels E being arranged in a circle so as by the step-by-step rotation of the disc to
come successively to firing position. The firing is effected by a wiper arm F fixed on
الله

page_text: shaft B and terminating in a wiper or finger which when the treadle A is depressed
moves in the same direction as the weighted arm C and trips the firing hammer G of
the cartridge chamber which was brought by the previous fall of the lever C into
firing position, each cartridge chamber being provided with a similar firing mechanism.
In order to concentrate the sound of the explosion in the required direction the
barrel when in firing position comes in line with a stationary trumpet mouth H
opening through the casing in which the apparatus is enclosed.
The angular motion of the main shaft B produced by the depression of the treadle
lever A is limited by stops a a beneath the latter, the spring A yielding to the wheel
flange when the rigid part of the treadle is arrested so that the full stroke is ensured
without danger of breaking the mechanism. The treadle lever when permitted to
assume the raised position is supported in such a way that it cannot be accidentally
depressed (by being trodden on for example) but can yield to the wheel of a train.
The treadle-supporting device consists of a hopper I pivoted at i to the treadle, the
rounded nose of the hopper being pressed by a spring i' into the notched butt j of a lever J
pivoted at and held down at its longer arm by a spring. The hopper I supports the
treadle by a direct thrust against the inclined abutment surface of the notch j the
inclination of the surface and the strength of the springs being such that the treadle
is supported immovably under the weight of a man but immediately the wheel comes
upon it the spring yields and the lever J tilts slightly so increasing the inclination
of the abutment surface of the notch j and allowing the hopper I to readily fly out of
the notch and the treadle to be depressed to its full extent. The raising of the treadle
to position to be acted on by the wheel is effected by the fall of the weight C' or the
action of its spring equivalent which is normally retained in readiness to so act by
means of a self-engaging catch K pivoted at k to the arm C and engaging with a
friction roller mounted on a fixed lug k³. The release of the catch can only be
effected from the signal cabin or other fixed point through a mechanical connection or
by preference electrically through an electro-magnet L. Accidental disengagement
of the catch K is prevented by a stop formed by a pendent arm pivoted at k* and
held by a spring with its lower end in position to arrest the catch. The release of
the catch is effected by the oscillation of a lever M pivoted at m and having two
arms m² m² of which m² lifts the latch whilst m' engages with a pin on the pendent
arm ³ and swings it aside, a third arm being connected through a link with the
armature of the electro-magnet. To work the apparatus mechanically the armature
lever is connected by a slotted link to one arm of a bell crank lever 1, the other arm
being connected by a pull wire to a lever handle (not shown) placed in any
convenient position. The arm m¹ of the lever M is longer than the arm m² and the
relative position of the arm m¹ and of the pendent arm on which it acts is such that
a slight clearance between the catch K and the stop k is sufficient to give the latter
time to be moved out of the way of the catch K so that it may be raised by the
The weight of the catch K is partially counterbalanced by a spring to
reduce the work of the magnet and when so disengaged the nose of the catch K slides
along the surface of the lug k³ on which it remains supported throughout the fall of
the weighted arm C in readiness to become re-engaged when the arm C is raised again
at the next depression of the treadle. To reduce as far as possible the weight of the
arm C necessary to impart the step-by-step rotation of the disc D the shaft B may be
mounted in ball bearings and the limitation of the motion imparted to the disc to the
distance of one tooth is effected by spring detents n pivoted to the arm C which press
against the cartridge barrels E as teeth, and act in the opposite direction to a
non-return pawl N engaging with the teeth of the disc so that the angular motion of
the disc cannot exceed that of the weighted arm C when falling, whilst on the return
motion of the weighted arm the spring detents n slip whilst the disc is held stationary
by the non-return pawl N.
arm m
The breech end of each barrel E is closed by a pivoted or other breech block e
having a firing pin e¹ in position to be struck by the firing hammer G pivoted in a
bracket carried by the breech block and acted on by a spring 9, the tail end of the
firing hammer projecting in the path of the wiper or finger f. When the latter is

page_text: oscillated in the direction of the arrow by the depression of the treadle A it trips the
firing hammer G with which it was engaged (the dise D being held against motion in
this direction by the pawl N) and the wiper then moves into position for engagement
with the firing hammer of the next succeeding barrel, these parts afterwards moving
together as one to the firing position the next time that the treadle is raised. In
order to indicate which cartridges have been fired, an arm g¹ is pivoted stiffly on the
hammer pivot, and is moved out by the hammer when the latter is raised by the
wiper and so remains after the hammer has fallen. In re-charging the disc it is
necessary to rotate it by hand and to permit of this without actuating the firing
mechanisms the wiper finger fis thrown out of acting position for which purpose it is
mounted on a base plate pivoted at f' to the wiper arm F and is held in position to
act by a spring bolt f
The energizing of the electro-magnet L in order to set the treadle in position to be
acted on, is effected by closing the circuit at a key O in the cabin and in order to
indicate the position of the apparatus and inform the signalman when it has been
properly set for action and of the number of cartridges remaining unexploded an
electric tell-tale or register, such as shewn in Figure 6, is provided in the cabin which
is actuated by the closing of one or other of two electric circuits by a circuit closer in
connection with the weighted arm C'. The tell-tale comprises an index lever P
oscillated in one or other direction by one or other of two electric magnets QR the
circuit of the one Q being closed between the contact q and the contact p carried by
the weighted arm when said arm reaches its highest position whereby the index
lever P is moved to the position denoting that the signalling mechanism is "off,"
whilst the circuit of the other magnet R is closed between contact and contact p
when said arm reaches its lowest position, whereby the index is moved to the position
denoting that the signalling mechanism is "set" or ready for firing. The contact p
is electrically connected with the index lever P which is provided with circuit breakers
whereby the circuit of the magnet by which for the time being the index is moved is
broken just before the index reaches its extreme position to which it is carried by its
own momentum. The circuit breakers consist of spring brushes connected with the
index lever which rub upon the terminal contacts q¹¹ of the electro-magnets QR
the contacts being so arranged with regard to the index lever that when the
latter is in either of its extreme positions it is in electrical connection with the
opposite electro-magnet ready to be thereby moved to the opposite position when
the circuit of that magnet is closed by the corresponding contact and the contact p.
When the index P is moved from the "set" to the "off" position it may either
strike a bell mechanically or may in the course of its movement temporarily close
at the circuit of an electric bell S to notify the signalman that the train has
depressed the treadle A and exploded the signal. The indicator denoting how many
cartridges have been exploded is a dial T bearing numbers which are consecutively
exhibited at an aperture in the casing, this dial being rotated to the extent of one
number each time the index lever is moved to the "off" position, by a spring pawl t
carried by the index lever engaging with ratchet teeth on the dial, a detent t¹ also
carried by the index lever limiting the movement of the disc, a non-return pawl t²
preventing retrograde motion of the dial when the index lever is moved to the "set"
position.
The whole of the apparatus above described may be installed in duplicate for each
line if it be required to signal both "Caution" and "Stop" by means of explosive
signals and an electric gong operated from the cabin would be provided at a suitable
distance beyond the signalling apparatus for the purpose of signalling the train to go
on again.
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. The herein described combination of apparatus operating substantially as specified
and controlled from a distance whereby explosive signals, are brought successively

page_text: into position to be fired by the depression of a treadle lever substantially as
described.
2. In the herein described explosive signalling apparatus the combination, with a
movable cartridge carrier and mechanism for firing the cartridges carried thereby, of
a self-acting propelment device for bringing the cartridges successively into firing
position, a treadle for setting the device in active position and for actuating the firing
mechanism, and retaining mechanism controlled from a distance for preventing the
setting of the treadle in operative position until the required moment substantially as
specified.
3. In the herein described explosive signalling apparatus the combination, with a
revolving cartridge holding disc, of a weight or spring operated lever adapted to
rotate step-by-step the cartridge holding disc for bringing the cartridges successively
to firing position, retaining mechanism controlled from a distance for preventing the
action of said lever until the required moment, and a treadle which is raised to
operative position by the said lever and by the depression whereof the lever is returned
to its active position and the firing mechanism is actuated substantially as described.
4. In the herein described explosive signalling apparatus the combination, with the
disc-operating lever, of retaining mechanism constructed and operating substantially
as described for preventing the action of said lever until the required moment.
5. In the herein described explosive signalling apparatus the combination, with the
revolving cartridge holding disc, of firing mechanism substantially as described and of
a treadle and ineans for actuating by the depression of the treadle the firing mechanism
which has been brought to firing position substantially as specified.
6. In the herein described explosive signalling apparatus the combination, with the
treadle, of detent mechanism substantially as specified for preventing accidental
depression of the treadle.
7. The combination, with the explosive signalling apparatus constructed to operate
as herein described, of electrical circuit-closing and indicating mechanism for releasing
the retaining mechanism of the cartridge disc operating lever, for verifying the proper
working of the explosive apparatus and for indicating when the apparatus requires
reloading.
Daeth o
1000
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.