Improvements in Railway Signalling Apparatus.
Year: 1892

page_text: Date of Application, 18th June, 1892-Accepted, 30th July, 1892
COMPLETE SPECIFICATION.
Improvements in Railway Signalling Apparatus.
I, THOMAS PARTRIDGE, of 3 St. David's Terrace, St. David's Hill, Exeter, in
the County of Devon, Signal Fitter, 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 improvements for giving intimation to a signalman,
or signalmen, in the event of a portion of a train breaking away or becoming
detached, and also prevents him lowering his stop signal in the rear box. It
further provides that although the stop signal may be replaced to "danger" yet
the lever itself operating such stop signal cannot be replaced to its full normal
position until the treadle has been depressed; while the lever is in this intermediate
position all conflicting levers are locked.
"
It serves as an intimation to the signalman that such break away has taken place,
in addition to the fact of his not seeing the tail lamp.
I can also arrange the sectional signal in the rear box, that when returned to
danger" is locked and is only released by the last vehicle of the train depressing
the treadle in the next section. Should a break away take place and the last
vehicle not arrive at the treadle to depress it then the stop signal remains locked.
The difference between this invention and other inventions for intimating to a
signalman that a train has not passed the sectional signal, consists in the fact that
with this invention it is absolutely necessary for the last vehicle to pass, thereby
intimating that a portion of the train has been detached.
This last portion of my invention is a further improvement upon the mechanical
means, but my invention as mechanically arranged may be fixed complete
in itself.
"
In order that my invention may be better understood and more readily carried
into effect I will proceed to describe the drawing hereunto annexed.
Figure 1 is a plan showing the ordinary rails and my special form of treadle or
depression piece, adjacent to the rails.
Figure 2 is a side sectional view through X-Y on plan.
Figure 3 is a side view of the rack and pinion with the cover piece on.
Figure 4 shows a side section, X-Y Figure 1, with the depression piece up ready
to be operated by the striking piece on the last vehicle.
Figure 5 is a plan of the tooth p showing the spring q.
Figure 6 is a plan with cover removed of the blade h showing the position of
pawl j.
Figure 7 is a side view of portion of a vehicle showing the arrangement of the
striking piece r.
a are the continuous rails, 6 the treadle or depression piece, c the locking piece,
d the rocking shaft on which the treadle piece 6 is centred and on which the locking
piece is keyed, d' is the arm of the rocking shaft, and e are the cross bar and
rod connections to the rack f, g is the pinion, is a sliding piece fixed at the side
of the pinion, and fulcrumed to the sliding piece is a pawl held in position by a
spring k.
The usual rod connections are provided from the end of the plate to the lever
in the signal box.
l
I is the locking piece fulcrumed to the base plate, its upper end l' interlocking
with a corresponding notch 2 in the plate c, and its lower end 12 is resting upon a
spring m. A plate o which forms the cover of the pawl and the spring fixed at
the side of the pinion has provided on it a tooth p, also kept in position by a spring q
operating in connection with the said tooth.

page_text: F
:
Ine working of my invention is as follows:
A train arriving at the stop signal adjacent to which the depression piece or treadle
is fixed, upon the last vehicle passing, the striking piece depresses the treadle band
allows the stop signal to be replaced to its normal position thereby freeing all
interlocking which was conflicting or levers which were conflicting in the locked
position. The signalman by being able to replace his lever to the normal position
gets information that the whole of the train has passed the treadle and therefore
no: break away has taken place.. Should, however, the stop signal be lowered: and
a portion of the train break. away before the train has arrived. at the treadle the
treadle itself will not be depressed and should the signalman fail to notice that the
train has no tail lamp in putting his lever back he can only replace it to an inter-
mediate position, enough to allow him to put the signal to "danger
"but not
release conflicting levers. This gives him intimation that a portion of the train
has broken away. It is his duty now to communicate with the rear signalman
informing him that a portion of the train has broken away. In order that the
lever may be replaced to its normal position either the next train must depress the
treadle or the signalman must go on the ground and depress it himself. Only
when the treadle has been depressed can the lever be replaced to its normal
position.
The normal position of the treadle is down. When the stop signal lever to which
the treadle is connected is operated, movement is given to the blade h,.the pawl. k is
in gear with the tooth of the pinion g, the pinion is revolved to a slight extent, sufficient
to reverse the cross bar and rod. connection e', operate the rocking shaft d'and. allow
the piece through the action of the spring underneath it to force the treadle
upwards. As soon as the treadle or depression piece is moved upward so as to be
in gear, the top projection l' is forced into the notch c² of the locking piece c; the
stop signal is now in the "all right" position and the treadle is in gear. Should a
break away take place as previously referred to the signalman is allowed to put his
lever back sufficient to put the arm to "danger." but not to free any conflicting
levers as it cannot be replaced to its normal position.. The reason why the lever
cannot be replaced to its normal position is that the pinion is not turned sufficiently
round 30 that the pin g' is free of the tooth p.. The lever is now in the locked
position and the signalman is informed that, some. accident has taken place. In
order to place, the apparatus in the normal position again the treadle has to be
deflected, and the operation of deflecting the treadle forces the projection on the
piece / out of the notch in the locking plate c and moves the rocking shaft.d, the
rod and cross bar connections e, and the rack f thereby slightly turning the pinion
round sufficient for the pin g¹ to be clear of the tooth p; the lever can, now be
replaced to its normal position.
Although I have described the striking piece on the last vehicle as being fixed
to the body of the carriage as shown in the illustration,. yet. it is obvious that such
arrangements may be provided that the striking piece may be fixed to the axle.or
the-underframe of the body of the carriage. as is desirable.
Figures 8 and 9 show a modification of my invention.
Figure 8 illustrates the apparatus in the normal position. When the rod is
operated in the direction of the arrow the signal. is lowered and the pin. v pushes the
piece u out of the way and engages in the notch t on the signal blade.
u
When the striker has gone over the treadle it forces the pin v under the piece
which is brought back by the spring to and allows the lever to be put back to its
'full position.
Figure 9 shows the apparatus in position to be operated by the striker.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed T declare that what I
claim is.:
:
I. In railway signalling, apparatus for intimating, to a signalman that a portion
of a train has broken away and has not passed the stop signal, thereby either

page_text: remaining in his section or travelling in the rear section on the wrong road,
substantially as illustrated on the accompanying drawing.
2. In railway signalling, apparatus whereby a stop signal lever operates a
depression piece or treadle to the extent that if the last vehicle fails to
pass over
the depression piece or treadle the stop signal may be replaced to "danger" but the
stop signal lever cannot be replaced to its normal position until such treadle has
been depressed, substantially as described and as illustrated in the accompanying
drawings.
3. In railway signalling, apparatus such as the pinion g and rack ƒ and the pawl
and tooth and springs in connection therewith for allowing a movement in one
direction but only a partial return movement sufficient to put the signal arm to
danger," substantially as described for the purposes specified and as illustrated on
the accompanying drawing.
66
4. In railway signalling, providing on the last vehicle of each train a striking
piece operating in connection with a depression piece or treadle substantially as
described and for the purposes specified.
5. In railway signalling, apparatus whereby a stop signal may be replaced to the
'danger" attitude but the lever itself operating such signal is prevented from
returning to its normal position thereby retaining any necessary interlocking of
conflicting levers, all substantially as described for the purposes specified.
6. In railway signalling, apparatus substantially as illustrated in Figures 8 and 9
of the drawing annexed, for allowing a movement in one direction but only a partial
return movement sufficient to put the signal arm to "danger," substantially as
described and for the purposes specified.
Dated this Eighteenth day of June 1892.
JOHN P. O'DONNELL,
2, Great George Street, Westminster, S.W.,
Agent for the said Applicant.