Improvements in Automatic Fog Signals.
Year: 1888

page_text: Date of Application, 10th Aug., 1888
Complete Specification Left, 10th May, 1889-Accepted, 22nd June, 1889
PROVISIONAL SPECIFICATION.
Improvements in Automatic Fog Signals.
HENRY TAYLOR GRUNDY Mining Engineer Radcliffe near Manchester Lancashire
do hereby declare the nature of this invention to be as follows :-
This invention has for its object improvements in Automatic fog signals for use on
railways, and consists in an air compressing Cylinder, fixed in the ground close to
and below the level of the rails, and is fitted with a piston and piston rod. The said
piston rod passes through the cover of the cylinder, inside the cylinder is a spiral
spring one end resting on the bottom of the cylinder and the other underneath the
piston. Outside the cylinder is fixed a whistle or fog horn, and at the bottom of the
cylinder is formed a passage which leads to the whistle or fog horn, and directly over
the air compressing cylinder is fixed a lever or treadle made in the form of an arc,
one end of it works on a fulcrum and the middle of it rests on the top of the piston
rod. At the other end is connected a wire which passes over suitable pulleys to
change its direction on its way to the signal, to which it is attached to a lever for
raising or lowering the lever or treadle when the arm of the signal is at danger or
right angles with the post. The lever or treadle will be raised about two inches above
the level of the rail, and when the flanges of the wheels of the Engine and carriages
runs over it, it will be forced down, thereby forcing the piston down in the cylinder
compressing the air which is in it and sounding the whistle or fog horn, giving the
Engine man warning that he is approaching a signal, and when the arm is lowered
down the lever or treadle is pulled down below the level of the rails by means of the
wire which goes to the signal. The Spiral spring which is inside the cylinder is for
the purpose of forcing the piston to the top of the cylinder every time it is forced
down, which will be every time a wheel passes over the lever or treadle. In the
cover of the cylinder is drilled several holes for the admission and emission of air as
the piston moves in a downwards or upward direction. This invention can be so
arranged as to give the Engineman warning for more than one signal in one post if
desired.
COMPLETE SPECIFICATION.
Improvements in Automatic Fog Signals.
I HENRY TAYLOR GRUNDY Mining Engineer, of Radcliffe near Manchester in the
county of Lancaster, 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 for its object improvements in Automatic Fog Signals for use on
Railways and in order that it may be fully understood I refer to the accompanying
drawings.
Fig. 1. represents one method of fixing and applying my invention.
Figs. 11. and III. represent in elevation and plan respectively another method of
fixing and applying my invention.
In Fig. I. A is a cylinder within which works a piston B. Below the piston is a
spiral spring C preferably of taper form so as to retreat within itself.
From the lower part of the Cylinder a passage within the pipe D communicates with
the whistle or fog-horn E.
The link or piston rod F is attached to the piston B and passes through the

page_text: Cylinder Cover Directly over the Cylinder in this arrangement the lever or
treadle G is fixed. It has the form of an arc and is binged at H as a fulcrum. The
middle part rests upon or is attached to the top of the rod F.
"
The mechanism as thus described is placed in a suitable position upon a line of
railway adjacent to a "distance or other signal and in such lateral position with
reference to the rails that the curved lever G lies on the inside or flange side of the
rail I. and within the range of lateral deviation of the wheel flange. It is also so
placed that the direction in which the trains travel is represented by the arrow with
respect to the relative positions of the fulcrum H and the upper portion of the lever
operated upon by the flanges of the wheels. In height the upper portion of the lever
is allowed to project about two inches above the level of the top of the rail. To the
end of the lever opposed to the fulcrum a wire or chain K is attached. The wire or
chain passes downwards to a pulley L and so to the side of the line. Its direction
may be changed as desired and it may be attached to the wire by which the before-
mentioned signal is operated from a signal-box in such a way that when the signal is
pulled down or "off" the lever is also pulled down. Or the wire of the fog-signal
lever may be operated independently from the signal-box or elsewhere as desired.
The action of the apparatus is as follows:-
Upon the passage of a train in the direction indicated by the arrow, the flange of
each wheel will depress the lever G if it has not previously been depressed by the
action of the signalman pulling down the wire or chain. The rapid action of the
passing wheel causing a sudden descent of the piston B creates an outrush of air by
the aperture to the whistle E and this is repeated as each wheel passes, the piston
being rapidly returned to its upper position by the spring C. Ample ingress and
egress for air above the piston is provided through the Cylinder Cover and the space
below the piston is recharged with air at each up-stroke by way of the Whistle itself
and its passage or by an inlet valve for the purpose. Thus a series of short sharp
sounds are given out and the driver is warned of danger ahead.
By the arrangement illustrated in Figs. II. and III. the same result is attained by
a somewhat different arrangement of the parts of my invention. In this case the
Cylinder A is mounted in an inclined position. B is the piston as before, C the
spring, D the connection to the whistle E and F the piston-rod. In order to get
the Cylinder into a more convenient position I use a rocking shaft M carried in
bearings N N. This shaft may be square or otherwise, but I attach to it the curved
lever G at a suitable angle and also the lever O which may be connected to the
piston-rod by a link P. as illustrated or the piston-rod itself may be a link as in
Fig. I.
The chain or wire K for pulling off the signal is shewn as before and in Fig. III. a
bellcrank is shewn by which its direction may be changed as before described.
The lever G is preferably made of laminated form as illustrated.
In some cases I make the pipe D of considerable length-prolonging it forward
along the line in the direction of the train's motion so that the sounds shall be
somewhat ahead of or partially alongside of the Engine as it passes the apparatus.
I wish it to be understood that I do not confine the form or application of my
invention to either of the precise forms herein described or illustrated in the drawings
herewith, but having now particularly described and ascertained the nature of my
said Invention, and in what manner the same is to be performed I declare that what I
claim is :-
1. An air-compressing Cylinder with fog-whistle or horn attached and whose piston
is operated by the wheels of a train passing the point where the said Cylinder is fixed
upon a line of railway substantially as and for the purposes herein before described and
illustrated in the accompanying drawings.
II. The air-compressing Cylinder with Spiral or other suitable spring, operating
upon the piston to produce a return stroke substantially as and for the purposes
hereinbefore described and illustrated in the accompanying drawings.

page_text: III. The curved lever projecting upwards into the line of travel of the flange of the
wheel substantially as and for the purposes hereinbefore described and illustrated in
the accompanying drawings.
IV. The chain or wire attached to the mechanism of the fog alarm whistle and so
arranged as to pull the same out of range of travel of the wheel when it is not desired
that the apparatus shall be operated by the train substantially as and for the purposes
hereinbefore described and illustrated in the accompanying drawings.
Dated this 8th day of May 1889..
EDGAR CONISTON MILLS,
Agent to the Applicant.