Improvements relating to Catch Points or Switches and Automatic Signals for Railways.
Year: 1893

page_text: Date of Application, 13:h July, 1893
Complete Specification Left, 13th Apr., 1894-Accepted, 19th May, 1894
PROVISIONAL SPECIFICATION.
Improvements relating to Catch Points or Switches and Automatic
Signals for Railways.
I, JOHN GEORGE DIXON, of Elm Cottage, Dry Clough Lane, Crossland Moor,
Huddersfield, in the County of York Spinner's Manager, do hereby declare the
uature of this invention to be as follows:-
This invention relates to means for controlling catch points or switches and
automatic signals on railways.
Catch points or switches as heretofore constructed are defective for the reason
that the controlling weight being constantly in operation acts to withdraw the
switch from the rail immediately after each wheel of the train passes clear of the
same, and consequently the switch is moved to and fro once for every wheel that
passes over it. The parts of the apparatus are thereby very much shaken and
severely used and are soon damaged or broken, resulting sometimes in accidents to
the trains. Similarly automatic signals controlled by inclined bars which are
depressed by the wheels of the passing train such for example as are used in
tunnels to indicate to the driver when he is approaching the ordinary line signals
have heretofore been so constructed that each wheel of the train works the signal
and therefore an unnecessary amount of wear and tear is caused in the apparatus
resulting in frequent breakages which sometimes cause accidents.
According to my invention I obviate these objections, by combining with such
switches or catch points and signal apparatus means whereby in the preferred
construction the switch or signal will be operated by the first wheel only of the
train, and therefore will only be operated once for each train instead of being
operated many times as has heretofore been the case. I sometimes however as
applied to signals so arrange that two or more signals shall be given.
For the above purpose I provide, in combination with the switch or catch
point or with the inclined bar by the side of the rails for working the signal,
a pneumatic or hydraulic check or equivalent device which so operates that when
the switch or inclined bar has been moved from its normal position of rest. by
the first wheel of the train it cannot return suddenly but is allowed to return very
slowly at a rate which is determined by the adjustment of the said checking
device. The type of checking device which I prefer to use is one that comprises
a cylinder and piston fitted with a valve or valves and having in some cases a
simple inlet or outlet unfitted with valves so arranged that the piston can be
moved very readily in one direction but will only move slowly in the other
direction depending on the rate at which air or liquid, as the case may be, can
flow into or out of the cylinder through the valves or through the inlet or
outlet. By this means, the too rapid return of the switch or inclined bar after it is
once operated is prevented, so that the said switch or bar rises or returns but a
very short distance before the next wheel comes in contact with same, and thus the
whole of the train passes before the switch or inclined bar can return to its normal
position.
As applied to signals of the kind above indicated I sometimes construct the
apparatus to sound more than once so that the guard who is frequently at the rear
end of the train may also be warned by the signal.
Dated this 13th dor of July 1202

page_text: COMPLETE SPECIFICATION.
Improvements relating to Catch Points or Switches and Automatic
Signals for Railways.
I, JOHN GEORGE DIXON, of 98 Norman Road, Birkby, Huddersfield, late of
Elm Cottage, Dry Clough Lane Crossland Moor, Huddersfield, in the County of
York, 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 :-
This invention relates to improvements for controlling catch points or switches
and audible signals on railways.
Switches, such as catch points or run-away traps, as heretofore constructed have
the disadvantage that the controlling weight being constantly in operation tends to
withdraw the switch from the rail immediately after each wheel of the train passes
clear of the same.
In the case of automatic audible signals the same objection takes place that the
treadle which is commonly used in connection with such signals is depressed by
every wheel passing over and consequently there is a considerable amount of
unnecessary work put upon the several parts of the apparatus.
According to my invention I obviate these objections by combining with such
catch or other points, and audible signal apparatus, means whereby in the con-
struction the switch or signal will be operated by the first wheel only of the train
and therefore will only be operated once for each train, instead of being operated
many times as heretofore.
In the matter of audible signals I sometimes arrange a swinging bell whereby a
continuous ring is given.
For the purposes above described I provide in combination with the catch switch
or point apparatus or with the inclined bar by the side of the rail, a pneumatic or
hydraulic check or equivalent device which so operates that when the switch (or
inclined bar in the case of audible signals) has been moved from its normal
position of rest by the first wheel of the train it cannot return suddenly but is
allowed to return slowly at a rate which is pre-determined by the adjustment of the
said checking device.
The form of checking device which I prefer to use is one that comprises a
cylinder and piston fitted with a valve or valves and having in some cases a simple
inlet or outlet unfitted with valves so arranged that the piston can be moved very
readily in one direction but will only move slowly in the other direction, depending
upon the rate at which air or liquid, as the case may be, can flow into or out of the
cylinder through the valves or through the inlet or outlet. By this means the too
rapid return of the switch or inclined bar after it is once operated is prevented, so
that the said switch or bar rises or returns but a very short distance before the
next wheel comes in contact with same, thus the whole of the train passes before
the switch or inclined bar can return to its normal position.
In order that my invention may be better understood and more readily carried
into effect I will proceed to describe the drawings hereunto annexed, in which
similar letters refer to similar parts or substitutes therefor in the different
"figures.
Figure 1 illustrates a cross-section of the permanent way and a part section of
one form of my apparatus for preventing the too rapid return of the switches to
their normal position.
→
Figure 2 illustrates a cross-section of part of the permanent way and an alternative
form of apparatus to that shown in Figure 1.

page_text: Figure 3 illustrates a cross-section of part of the permanent way and my
apparatus for operating a gong or audible signal and arranging for a prolonged
signal.
Figure 4 is a plan of Figure 3.
Figure 5 illustrates a part section of the permanent way and that form of my
apparatus for giving only one sound on the gong or bell, that is, a short signal in
contra-distinction to the continuous or prolonged signal illustrated by the apparatus
in Figure 3.
Figure 6 is a part plan of Figure 5.
The way in which I carry out my invention is as follows:-
Referring to Figures 1 and 2 in connection with switch points, a is the sleeper,
the stock rail, the switch rail, the connecting rod from the switch rail,
d, d' the lever, d² the counter-balance weight, e is the piston rod, e is the tappet
attached to the piston rod terminating in a guiding end e², e³ is the slide working
in the said guiding end e², et es are adjusting nuts on the slide e³f is the piston,
g the cylinder, the side tube, g' the spring valve of which is the spring,
his a hole or aperture on the upper side of the cylinder on which is a ball
valve h¹.
Referring to Figures 3 and 4 of my apparatus for a continuous audible signal,
a is the sleeper, b the rail, z the treadle bar fulcrumed at one end. below rail
level (see Fig. 4) and at the other end being above rail level to be struck by the
first wheel of the train passing over it; is the transverse lever (connected to a
piston) similar to Llever d, din Figures 1 and 2; i is a bell attached at the end
to a spring barj, the lower end of the spring bar j is held and retained in an
upright position by the carriage k, 1 is a bracket attached to the spring rod j and.
fulcrumed to this bracket is a pawl or catch its end 12 being weighted. The
lower inner side of the bracket offers an obstruction so that the weighted end /*
cannot fall below the inner side of the bracket. The end of the pawl is
arranged with a projecting piece which is struck by the upward movement of the
eud of the lever a.
n²
Referring to Figure 5 of my arrangement for producing a single sound on a
gong or bell, m is a gong fixed in a suitable position, n is a lever fulcrumed
at n the striker n³ being at one end, the other end having a balance weight n
attached to it, o is a pawl with a projecting stop o' at one side the other projecting
end o² being formed into an engagement arm for contact with the end d³ of the
transverse lever x.
The action of that portion of my invention referring to run-away catches is as
follows:-
A train or vehicle approaching in the trailing direction of the switch moves the
points, raises the balance weight d² and piston f, the piston is allowed to move
rapidly upwards by the air being sucked from the side tube 9' and the valve
being drawn downwards, the air is forced out of the upper side of the cylinder
through the aperture' and as long as the wheel is travelling between the switch
and the stock rail the switch cannot return to the normal position, the return motion.
of the switch is retarded in consequence of the air having to escape by leakage
from the under side of the piston to the upper side of the cylinder the ball valve h
closing the aperture on the top and the spring closing the valve g². In the normal
condition the adjusting nut et is on the top of the valve 2 keeping the said valve
open during the upward movement of the piston but when the termination e² of the
tappet el (refer to Fig. 1) approaches and comes in contact with the upper nut e³,
during the remaining upward motion the slide e³ is moved upward and away from
the valve g² consequently on the return motion the valve g² is closed by means of
its spring 93 until the lower adjusting nut e comes in contact with the top of the
valve g which instantaneously admits air and allows the final movement in the
return of the switch to its normal position to be completed rapidly. The balance
weight acts to return the switch and force the piston down.
In Figure 2 is shown an alternative form of dash-pot, the upper cover over

page_text: the cylinder acting as a balance weight in lieu of weight d². In this figure
fis a valve in the lower side of the piston which allows the piston to be moved
rapidly upwards; the valve is closed on the downward motion and the return
of the switch to the normal position cannot take place until the air has leaked
from the lower to the upper side of the piston.
I will now describe the action of my apparatus for operating gongs or bells in
connection with railway signalling, shown in Figures 3 and 4. In these figures
a treadle is fulcrumed at z¹ its other end being raised above the rail so as to
be struck by the wheel of a passing train. When the said treadle is struck
downwards the transverse lever a corresponding to d, d¹ in Figures 1 and 2, is
moved so that its end rises and draws the piston up. By the upward motion of
the end d³ of the transverse lever the projection of the pawl is struck
and the weighted end offering an obstruction the whole bar j is vibrated so
that the bell is sounded. On the downward motion of the end d³ of the
transverse lever, through the action of the air escaping from the lower to the
upper side of the cylinder, the end of the said transverse lever strikes against
the end of the pawl and tilts it but does not effect any further motion on
the bell.
In Figures 5 and 6 is illustrated an arrangement for giving one sound only,
that is to say, the gong m is struck once during the passage of a train. The
action is somewhat similar to that described in reference to Figures 3 and 4.
On the treadle being depressed the further end of the transverse lever x is
moved upward carrying the piston, and its end d³ strikes against the projection o²
of the pawl o thereby forcing down the striking end of the lever n by means of
the projection o¹ and carrying upward the weight n²; upon the end of the
transverse lever passing the projection o² the weight n falls and the end n³ strikes
the gong m.
On the downward motion of the transverse lever, through the action
of the air escaping from the lower to the upper side of the piston, the end o² of
the pawl o is simply tilted which action does not make any sound on the gong.
Although the alternative form of dash-pot illustrated in Figure 2 is shown in
Figures 3, 4 and 5, yet that form as illustrated in Figure I may be used if
desired.
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. In connection with self-acting switches on railways arranging an air cylinder
and piston, operating that the switches are free to be moved rapidly from their
normal position by the first wheel of the engine, but cannot return to their normal
position until the last wheel of the train has passed clear and the piston returned
normal, substantially as described and illustrated in Figures 1 and 2 of the
drawings annexed.
2. In audible railway signalling apparatus the combination of a treadle, air
cylinder and piston, a transverse lever for sounding a bell on the passage of the
first wheel of an engine or vehicle over the said treadle in the running direction,
substantially as described and illustrated in Figures 3 and 4 of the drawings
annexed.
3. A treadle for use in audible railway signalling apparatus, which on being
depressed by the first wheel passing over it is put out of contact so as not to be
again struck by the remaining wheels of the train and only returns to its normal
position when the piston f returns normal, substantially as described and illustrated
in Figures 3 to 6 of the drawings annexed.
4. In audible railway signalling apparatus, an air cylinder and piston preventing
the operating end of the transverse lever from performing more than one
upward movement (for sounding a gong or bell) substantially as described and
illustrated in Figures 3 to 6 of the drawings annexed.
5. In audible railway signalling the combination of apparatus for sounding a

page_text: gong by the passage of a train, substantially as described and illustrated in.
Figures 5 and 6 of the drawings annexed.
Dated this Thistoonth day of Anril 1804
JOHN P. O'DONNELL,
Agent for Applicant.