Improvements in and relating to Fog Signal Apparatus for Railways.
Year: 1893

page_text: Date of Application, 20th Dec., 1893-Accepted, 20th Jan., 1894
Improvements in and relating to Fog Signal Apparatus for
Railways.
I, WILLIAM WELLS of 31, Barnsdale Road, Harrow Road, Paddington, London,
Gentleman, 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 fog signal apparatus for railways
of the kind referred to in my former Letters Patent No. 16846 dated the
7th of September 1893 and which consists of apparatus for placing fog-signals
or detonators upon the railway line by means of a special lever and connections
from the signal box or other convenient position. The fog signals are in the form
of rectangular blocks and are placed in a line contiguous to one another in an oblong
rectangular metal box or casing provided with a cover and fitted with a lock whereby
the box may be opened for filling it and securely closed again. At one end of the
box is fitted a coiled spring roller to which are connected the two ends of a cord or
chain passing over pulleys at the other end of the box, and around small pulleys
or rollers carried by a sliding block or pusher bearing against the rearmost signal or
detonator so as to press the said signals forward as each is pushed out of the box.
The foremost end of the box carries a steel block or propeller capable of sliding in
guides fixed at right angles to the box and to the line of rails, the front end of the
propeller being recessed to receive the foremost signal and to push it on to the rail
when operated from the signal box or other position. The fog-signals are partly
formed of a wooden block having in its upper surface a notch for receiving the end
of a small spring fixed to the top of the box so as to prevent the detonator being
drawn back into the box when the signalman pulls the propeller back into the said
box and also for holding the said signal firmly on the line. An electric indicator
in the signal box gives warning when the fog-signal box is nearly empty.
Now according to this my present invention instead of fitting a coiled spring
roller at one end of the signal containing box I pass the cord or chain connected
to the sliding block or pusher through one end of the box and around a guide
pulley to another guide pulley from whence it passes to a pulley carried by a post,
its end being fastened to a weight which acts upon the sliding block or pusher 50
as to press or feed forward the detonators contained in the box in a similar manner
to the spring roller described in the Specification of ny aforesaid former Patent.
The bottom of the guide, containing the detonators, is formed with a longitudinal
slot for permitting the travel of a guide pin attached to the sliding block or pusher
and one end of the cord or chain is attached to a block or nut formed with or
screwed to the lower part of the said guide pin. The top edge of one side of the
guide is formed with a flange or projecting lip for preventing the detonators from
rising when pressure is brought to bear on them, and the explosive part of the said
detonators is fixed to the wooden part by means of a sheath or tube of thin metal
or other suitable material fitted to and projecting some little distance from the front
end of the said wooden part. In all other respects my present invention resembles
that described with reference to my aforesaid former Letters Patent.
And in order to more clearly understand my said invention and the manner of
carrying it into practical effect I will describe the same with reference to the

page_text: accompanying sheet of drawings in which like letters of reference refer to similar
parts throughout the figures.
Fig. 1 is a plan of the detonator box with the cover removed and Fig. 2 is a
longitudinal section thereof.
Fig. 3 is a cross section of the box, and
Fig. 4 is a section of the signal propelling box or guide showing a fog-signal_in
position on the line for being acted upon or exploded by the passage of an engine
the dotted lines indicating the propeller drawn back ready for pushing a fresh
signal on to the line.
Fig. 5 shows a section of one of the detonators.
At one end of the detonator box a is fixed a guide roller c around which passes
the cord or chain d which latter also passes underneath a guide roller c² fixed to
a post or upright P, and from thence over another pulley likewise carried by the
post P, its end being attached to a weight W.
The other end of the cord or chain is passed over a pulley e revolving on bearings
at the other end of the box a and is attached to a block or nut 93 secured by the
pin g³ and nut g* to the sliding block or pusher 9, a* being a slot formed in the
bottom of the guide a¹ for permitting the passage or travel of the said pin g³. One
side of the guide a¹ is formed with a flange or lip a' for preventing the detonators b
rising out of position during their travel along the guide a'. ' represents a metal
case, provided with a cover which may surround the post P and the mechanism
connected to it to preserve them from the effects of the weather. It will be evident
that instead of employing the post P the weight W may be arranged to work in a
hole or pit below the level of the ground. Fig. 5 shows a section of one of my
improved detonators in which the part 62 is constructed of wood and has attached to
its forward end a thin metal or other sheath or short tube 68 forming a recess into
which is fixed the exploder b. This enables a fresh detonator to be fixed to the
parts 63, 6 after it has been exploded by the passage of a train or engine.
The operation of my improved apparatus is as follows :- When the signalman
pulls over the lever to indicate that a train may pass and should the signal at the '
time be invisible through fog or otherwise, he likewise pulls over the lever operating
the propeller thus pushing the end detonator out of the box a on to the line u
as represented in Fig. 4 so that the detonator is exploded on the passage of
the engine over it thus indicating that the train may pass the signal. When
the fog-signal lever is reversed it draws back the propeller into the position
shown in dotted lines the disabled detonator being prevented from being drawn
back with it by means of a small spring fixed to the cover a³ of the guide a
and entering
a notch b¹ formed in the rear part of the detonator; the part 6'
then falls down by the side of the line and may be made use of again by
affixing it to a fresh detonator.
When all the detonators have been used the pusher g is pushed back to its
starting position where it may be fixed by a pin gl secured by a chain g³ to
the box a and fresh detonators placed in the box a, the cover a being removed
for this purpose; the said cover is placed again on the box where it may be
secured by a lock a³, the pin g¹ being previously removed.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In fog-signalling apparatus for railways the combination with the sliding
block or pusher g of the cord d, the pulleys c, c', c³, weight W, post P, and
case substantially as described and for the purpose specified.
2. The combination with the guide a' of the slot a formed therein, the guide
pin for guiding the pusher 9 and the lip or flange a' for keeping the
detonators 6 in position in the said guide substantially as described and shown
in the accompanying drawings.

page_text: 3. The improved detonator or fog-signal substantially as shown in and described
with reference to Fig. 5 of the accompanying drawings.
Dated this 15th day of December 1893.
F. G. CASSELL,
Of Cassell & Co.,
22, Glasshouse Street, Regent Street, London, W.,
Agent for the Applicant.