Improvements in Fog Signalling Apparatus for Railways.
Year: 1891

page_text: Date of Application, 16th Jan., 1891
Complete Specification Left, 4th Nov., 1891-Accepted, 5th Dec., 1891
PROVISIONAL SPECIFICATION.
Improvements in Fog Signalling Apparatus for Railways.
We, HARRY LOUIS DAVIS, Assoc. M. Inst. C.E. of 108 Romford Road,
Stratford, E. and ISAAC FRANCIS TAYLOR of No. 1 Prospect Terrace, White
Post Lane, Manor Park in the County of Essex, Wheelwright, do hereby declare
the nature of this invention to be as follows:-
For
but to be
Our invention relates to apparatus whereby successive fog signals are exploded
on passage of successive railway trains past a signal standing at "danger."
this purpose, we place the apparatus by the side of the line near the signal and we
arrange in connection with it a treadle or trigger operated on by passage of a train
so as to act on the apparatus when the signal stands at "danger
inoperative on the fog signal apparatus when the signal stands at "safety." The
movement of this treadle or trigger is communicated to a rocking shaft which by
its stroke raises a hammer and allows it to drop, and also moves a slide whereby
the lowest of a number of fog signals, held in a chamber, is pushed on to an anvil
under the hammer to be exploded by the fall of the hammer.
In cases where a large number of fog signals may be required, we provide
additional compartments, each containing a pile of signals, these compartments
being circularly arranged in a cylindrical casing which by the action of the treadle
or trigger is moved step by step so as to bring these compartments in succession
over the chamber whence the fog signals are successively drawn to be exploded,
thus feeding the chamber from these compartments. Apparatus such as is above
described may obviously be used at any part of a railway line where it is desirable
to give warning in foggy weather, whether it be in the neighbourhood of one of
the ordinary signals or not. In the latter case the apparatus may be rendered
operative or inoperative by means of a pull or other connection from the signal
cabin.
Dated this 16th day of January 1891.
ABEL & IMRAI,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Fog Signalling Apparatus for Railways.
We, HARRY LOUIS DAVIS, Assoc. M. Inst. C.E. of 108, Romford Road,
Stratford, E. and ISAAC FRANCIS TAYLOR of No. 1, Prospect Terrace, White
Post Lane, Manor Park in the County of Essex, Wheelwright, 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:-
"
Our invention relates to apparatus whereby successive fog signals are exploded
danger.' For
on passage of successive railway trains past a signal standing at
this purpose, we place the apparatus by the side of the line near the signal, and we
arrange in connection with it a treadle or trigger operated on by passage of a train

page_text: so as to act on the apparatus as we shall describe referring to the accompanying
drawings.
Fig. 1 is a side view partly in section shewing the middle part of the
apparatus,
Fig. 2, is a plan,
Fig. 3, is a transverse section on X X of Fig. 2, and
Fig. 4 is a side view shewing the pawls for throwing the apparatus into or out
of use.
The treadle or trigger operated on by the train is connected to a rocking shaft A
causing it to rock when a train passes over the treadle so that its arm B makes a
stroke to the right and is brought back by a counterweight C.
On the arm B are mounted three rollers, of which is under a pawl D,
12 is under a pawl E and 63 is under a pawl F. The pawl D which has an
incline on its face is pivotted by a pin d on the side of a lever G which
terminates in a hammer head g and which has linked to it by two side links g' g³
the middle of a double sway beam H'H'.
The upper ends of these sway beams are pivotted at their lower ends are
linked to a double slide consisting of an upper plate K¹ and a lower plate K² which
can slide, the one above, the other below a fixed plate L, the lower plate K' running
on a roller and between a pair of rollers k¹. A number of fog signals S are
superposed in a tube T the lowest one resting on the plate L. M is an anvil and
N is a receptacle for the fired signals.
The levers E F and G are pivotted on a standard O and on another standard Q
is pivotted a bell crank lever P which has in its upper arm a pin p working in a
slot of the lever F, and which has its lower arm connected by a wire or other pull
to a suitable lever in the signal cabin.
The tail e of the lever E is connected to a treadle or trigger situated at some
distance greater than the length of a train beyond the treadle or trigger near
the signal post, and on the front end of the lever E is mounted a pawl e' which
is in the path of a roller on the pin p. It being understood that the treadle or
trigger near the signal post is so arranged that when a train passes over it, it
noves the shaft A when the signal is at "danger" but that it does not move A
when the signal is at "safety," it being also understood that there is a supply of
signals S in the tube T and that the pawl levers E and F are in the position shewn
in Fig. 4, the apparatus works in the following manner. When the first wheel of a
train acts on the treadle at the signal the arm B makes its stroke to the right, its
roller acting on the incline of D raises the lever G lifting its hammer end and
at the same time causing the slides K K to make their stroke to the left, whereby
the lowest fog signal S in the tube T is advanced by K' along the incline of L and
lodged on K. The roller having passed D, the lever G descends moving back
the slides KK2 so that the fog signal S¹ is deposited on the anvil M and is fired
by the descent of g. When the operation is repeated the slide K' by its advance
to the left pushes the fired signal into the receptacle N.
g
The arm B having moved to the right for the firing of one signal cannot return
because its roller is caught in front of the face e of the pawl E; consequently
the successive wheels of the train as they pass over the treadle do not fire successive
signals. But when the train has advanced to the distant treadle which is connected
to e, then the pawl E is raised and the counterweight C brings back the arm B to
the operating position, the pin carrying the roller & moving along the incline on
the face of D and pushing D aside until B has completed its back stroke allowing D
to fall back in front of br.
When the apparatus has to be thrown out of action, as when fog disappears, the
signalman releases the lever P the upper arm of which drops bringing down the
lever F so that its face f falling behind the roller ', when B has made its stroke
to the right, prevents B from making its back stroke notwithstanding that E is
raised by the action of the distant treadle.
The pin and roller p in descending thrusts the pawl e¹ aside but lodges under it

page_text: so that when the signalman again pulls P so as to put the fog apparatus into
working condition p acting under e¹ raises the lever E allowing B to make its back
stroke and then escapes from under e¹, allowing E to descend again to the
working position shewn in Fig. 4.
When it is desired to accommodate a large number of signals, instead of
employing a tube T, we provide a number of compartments arranged circularly
within a cylinder mounted on a vertical axis, each of those compartments containing
like the tube T a number of superposed signals S. By means of a ratchet and
pawl worked from any convenient part of the hammer and slide gear, the cylinder
at every operation of these parts is turned step by step bringing always one of its
compartments into the position of the tube T, so that the lowest signal in that
compartment is pushed out by the slide K'.
Although we have described the fog signal apparatus as being worked in con-
junction with an ordinary signal in its "danger condition," obviously it might be
situated at any part of a railway line and worked independently of the signal,
being rendered operative or inoperative at will by means of the pull acting on the
lever P.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, we declare that we are aware
that it has been proposed to arrange mechanism to be controlled or set by the
signalman by which a railway train on passing over or operating a contact
apparatus arranged alongside the line will cause detonating fog si nals fed from a
reservoir to be exploded between a hammer and an anvil and that we make no
general claim to such arrangement but what we claim is :-
1. Fog signalling apparatus for railways constructed and operating substantially
as herein described with reference to the accompanying drawings.
2. The combination of the treadle moved arm B, pawl D the hammer lever G,
the slides K' K' and their connections to G with the tube T or its equivalent
containing a store of fog signals, the plate L and the anvil M substantially as
described.
3. The combination of the treadle moved arm B and its operating treadle, the
pawl lever E and its distant releasing treadle substantially as and for the purpose
set forth.
4. The combination with the treadle moved arm B and pawl lever E, the
second pawl lever F and bell crank P with its pull or equivalent connection to a
signal cabin, substantially as and for the purpose set forth.
Dated this 4th day of November 1891.
ABEL & IMRAY,
Agents for the Applicants.