An Improved Apparatus for Automatic Fog Signalling on Railways.
Year: 1893

page_text: Date of Application, 2nd Sept., 1893—Accepted, 14th Oct., 1893
COMPLETE SPECIFICATION.
An Improved Apparatus for Automatic Fog Signalling on Railways.
I HENRY FROST CLARK, of Easton in the State of Pennsylvania, United
States of America, temporarily of 70 & 71 Palace Chambers, Bridge Street,
Westminster in the County of Middlesex, in England, Mechanical Engineer, 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 :-
My invention has reference to an improved apparatus for automatic fog signalling
on railways.
"
In previous efforts in this direction, apparatus has been devised for operating
with the signal connection for the distant or home signal, or any signal, so that
the detonator is in position on the rail when the signal is in the "danger
attitude and is removed therefrom when the signal is deflected to the "safety"
attitude.
With my apparatus
arrange that it is automatic in action and that a detonator
is exploded irrespective of the position of the signal arm, that is to say, that the
first wheel of the engine explodes the detonator and the apparatus works that no
second explosion takes place unless desirable. Immediately the last vehicle passes
over the apparatus it automatically places another torpedo in position to be
exploded.
In order that my invention may be better understood and more readily carried
into effect I will proceed to describe the drawings bereunto annexed.
Figure 1 illustrates a cross section of my apparatus with only a portion of the
detonator tube shown; the portion not shown is simply a continuation of the tube
and spring.
Figure 2 illustrates a section A'-A¹ of Figure 1.
Figure 3 is a part plan of Figure 1 with the magazine tube removed and the
cover on the left hand side also reinoved.
Figure 4 is a view showing the method of connection to the rail and also
illustrating the spring underneath the anvil for allowing for worn tyres.
Figure 5 is a plan of Figure 4 with the top of the rail removed, showing the
method of clipping the web. The magazine t is not shown in this figure.
Figure 6 illustrates a sectional view of the connection to the lever b viewed
from the front of the rail. This illustrates the spiral spring e contained in the
barrel n, referred to hereafter.
Figure 7 is a view of the lever b and the top braker on the wheel l.
Figure 8 is a plan view, partly in section, of Figure 7.
Figure 9 is a sectional elevation B-B2, of Figure 1, looking towards the end
of the machine away from the rail.
Figure 10 illustrates the slide or torpedo carrier for carrying the torpedoes from
the magazine under the exploder or hammer.
Figure 11 is a side view of the brake j.
Figure 12 is a plan view of Figure 11, partly in section, showing the spring at
the termination.
Figure 13 is a plan view partly in section, showing the cog wheels and the
connection from the crank o, which connection works in the slot p Figure 1.
Figure 14 is an elevation of the cog wheels.
Figure 15 shows the rail and a sectional view of the lifting bar k; the said bar
is lifted automatically above the rail to be in contact for the tread of the wheel,
by the spiral spring held in each clip.

page_text: Figure 16 is a side elevation of the lifting bar and clip.
The same letters refer to the same parts in the several figures of the drawings.
a Figures 1, 2, 3, 4, is the hammer or exploder, which when the machine is
ready for explosion, stands half an inch above the rail, and is forced down by the
first wheel of the locomotive which strikes it, exploding the torpedo under it, and
raising the lever.
b Figures 1, 2, 3, 6, 7, 8, 14, which is attached to the hammer a by the bolt c
Figures 1, 2, 3, 4, 7 and 8, and pivoted at d Figures 1, 3, 4, 7 and 8 compressing
the spiral spring e in the barrel or casing n shown in Figure 6, and lifting the
presser Figures 1, 7, 8 and 14 attached to the lever b by the bolt g, bringing it to
bear on one of the nine bolts in the gear wheel Figures 1, 13 and 14. The
presser fis provided with a spiral spring i shown in Figure 7, when the presser
is raised to the position shown in Figure 1. the spring by its bearing against the
under side of the lever b pushes the presser forward over the bolt in the gear
wheel h. The machine is now ready to load itself for the next train, but by the
means of brake j, Figures 1, 3, 6, 9, 11 and 16, it is held in this position while
the train is passing, operated by an automatic lifting bar k, shown in Figures 1, 3,
11, 12, 15 and 16. As soon as the train has left, the bar is moved to its position
shown by the dotted lines in Figure 16, drawing with it the brakej from the
friction wheel Figures 1, 13 and 14. The lever is now drawn down by the spiral
spring e, and by the presser f the gear wheel h is moved sufficient to change the
position of the bolts in the same one point, imparting to the second gear wheel m
Figures 1, 13 and 14, one revolution, when the lever is stopped from further
movement by coming in contact with the cover of the spring barrel n, shown in
Figures 1, 3, 6, 9, 13 and 14; to the axle of the second gear wheel m is attached
a crank o Figures 1, 3 and 13, and travelling in the slot of the slide attachment p
Figures 1, 3, 10 and 13, one half its revolution draws the slide q Figures 1, 2, 6, 9
and 10 back to the magazinet Figures 1, 3, 4, 6 and 9 to receive another torpedo,
and the remaining half of its movement pushes the slide forward, moving with it
the torpedo under hammer a. To the lever b at its rear is attached an arm r
Figures 1, 7 and 8, provided at its rear with an adjusting screw, to come in
contact with the friction wheel when the lever 6 strikes the cover of the spring
barrel 71, thus stopping further movement of the wheels. To the friction wheel
are attached fans to regulate the speed. The brakej is provided with a spiral
spring to hold the machine from reloading with more or less movement of the
lifting bar k.
The attachment of the machine to the rail is plainly shown in Figures 4, 5, 15
and 16. The working parts are all enclosed from water and dust, and the machine
is calculated to run without oil.
The torpedoes are forced through the magazine by a spiral spring t¹, shown in
Figure 1. By removing the bolts v Figures 3, 4, 5, 6 and 9, the top part of the
machine can be taken off, and with it the slide and all other moving parts.
When the machine is not required it is thrown out of function through the
lifting bark being held below the top of the rail by turning two buttons Figures 15
and 16 and marked z.
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 1
claim is :-
1. An improved automatic fog signalling device arranged substantially that one
or more (being a specified number) detonators are exploded by the passage of a
train or vehicle over the said apparatus, the apparatus being recharged after the
last vehicle of the train has passed clear of the apparatus, all substantially as
described and as illustrated in the accompanying drawings.
2. In automatic fog signalling, the combination of apparatus substantially as
described and as illustrated in the accompanying drawings.

page_text: 3. In fog signalling apparatus for railways the arrangement of the lifting bar
and the operation in connection therewith of the brake upon the friction wheel
attached to the gear wheels so that one explosion only takes place as illustrated
upon the drawings annexed and substantially as described.
Dated this Second day of September 1893.
JOHN P. O'DONNELL,
70 & 71, Palace Chambers, Bridge Street, Westminster, S.W.,
Agent for the said Applicant.