Improvements in Railway Point and Signal Apparatus.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Railway Point and Signal Apparatus.
We, JOHN WILSON, of The Firs, South Woodford, Essex, Engineer, HENRY
ALEXANDER GEORGE SHERLOCK, of 42, Lyndewode Road, Cambridge, Civil
Engineer, and WILLIAM PUGH, of 19, Ross Street, Mill Road, Cambridge, Signal
Fitter, do hereby declare the nature of this invention to be as follows:-
"
This invention relates to apparatus for locking railway points and "detecting
signals, and has for its object to guard against the possibility of the points not
being properly set in consequence of breakage of any of the operative connections,
by rendering the operation of the signals dependent on the setting of the points
so that no signal can be given except that which corresponds to the position in
which the points are set and locked.
The invention consists essentially in so connecting the plunger or bolt by which
the points are locked, the locking bar (by which the unlocking of the points is
prevented during the passage of a train), and one member of the "detector"
apparatus by which the working of the signals only in conformity with the setting
of the points is determined; the divided locking stretcher connecting the switch
tongues and engaged by the locking bolt, being connected to the other member
of the "detector so that motion will be communicated in the first instance
directly to the locking bolt, from thence to the locking bar, and from thence to
the member of the "detector" which is connected thereto, the other member of
the "detector" being moved by the setting of the switch.
The connections are made by suitable rods and levers in such manner that
should either the plunger, the locking bar, or the switch tongues fail to be
operated at the proper time in consequence of the breakage of a connection, the
detector" slides will also fail to be operated and consequently the signal allow-
ing a train to proceed cannot be given.
66
In order to render impossible the unlocking of the points, or the giving of a
conflicting signal should a connection break (between the plunger and the lock-
ing bar or between the locking bar and the rod through which the one member
of the "detector" is actuated) when the plunger is home, the "detector" actuating
rod or a part carried thereby is itself caused to act as a sort of "detector" for the
plunger, as for example by a lug on the latter being timed to coincide with and
pass through a notch on the former, when the two are moved concurrently cach
across the path of the other as in normal working, whereas should the rod fail to
be moved it will prevent the plunger being withdrawn to unlock the points.
The detector comprises two (or more) juxtaposed sliding members or plates
having as many sets of notches as there are signals to be controlled by it, said
notches being adapted, when the notches of a set coincide, to give passage to a
slide bar moved by the wire for lowering the signal to which that set corresponds.
These two notched plates or members have their sets of notches alternately on the
one and the other edge, adjacent slide bars being on different levels to corre-
spond, so that the notches of adjacent sets will be quite distinct in all positions of
the notched plates. The said notched plates are moved the one from the plunger

page_text: locking bar and the other from the switch locking divided stretcher as above
mentioned, to such extents that when the one plate is moved by the unlocking of
the switch none of its notches will coincide with notches of the other plate and
when the other, notched plate is moved in turn by the setting of the switch in
another position none of the notches in the two plates will coincide and no
signal can yet be lowered. But on the switch being locked in the new position
in which it has been set, those notches in the plates which correspond to a
particular signal will coincide and give passage to the sliding bar to which the
operating wire of that signal is connected, so as to permit of that signal being
lowered to denote that the points are set for a train to proceed on the road for
which the points are set, all other signals controlled by that detector being
maintained at danger.
Dated this 4th day of January 1899
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.
Improvements in Railway Point and Signal Apparatus.
We, JOHN WILSON, of The Firs, South Woodford, Essex, Engineer, HENRY
ALEXANDER GEORGE SHERLOCK, of 42, Lyndewode Road, Cambridge, Civil
Engineer, and WILLIAM PUGI, of 19, Ross Street, Mill Road, Cambridge, 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:-
"
This invention relates to apparatus for locking railway points and "detecting"
signals, and has for its object to guard against the possibility of the points not
being properly set (in consequence of breakage of any of the operative connec-
tions) by rendering the operation of the signals dependent on the setting of the
points so that no signal can be given except that which corresponds to the position
in which the points are actually set and locked, notwithstanding that the signal-
man may be under the belief that the points have been set and locked in another
position but have failed so to be in consequence of a breakage of an operative
connection.
"
The invention consists essentially in connecting the plunger or bolt by which
the points are locked, the locking bar (by which the unlocking of the point
locking plunger or bolt is prevented during the passage of a train), and one
member of the detector" apparatus by which the working of the signals in
conformity only with the setting of the points is determined, so that motion will
be communicated in the first instance directly to the locking bolt, from thence
to the locking bar, and from thence to the member of the "detector" which is
connected thereto, the divided locking stretcher which connects the switch
tongues and is engaged by the locking bolt, being connected to the other member
of the detector" which is therefore moved by the setting of the switch.
The connections are made by suitable rods and levers in such manner that
should either the plunger, the locking bar, or the switch tongues fail to be
operated at the proper time in consequence of the breakage of a connection, the
"detector" slides will also fail to be operated and consequently the signal
allowing a train to proceed cannot be given.
The invention will be described with reference to the accompanying drawings
forming part of this specification wherein Figure 1 is a plan of the point locking

page_text: and signal "detector" apparatus showing the connections of the parts. Figure 2
is a cross section shewing the auxiliary detector for the point locking plunger or
bolt. Figure 3 is a plan and Figures 4 and 5 side and front elevations of the
signal detector apparatus on a larger scale. Figure 6 is a diagram showing on a
still larger scale the successive stages in the operation of the detector slides
incidental to the setting of the main line points, and the signals corresponding
to the roads shown in the diagram Figure 7.
Referring to Figure 1, A is the main road denoted by the numeral 3 in the
diagram (Figure 7) and B are the switch tongues at the point of junction with
that road of the branch leading to the roads numbered 1 and 2, the switch
tongues being connected by a divided stretcher C adapted to be engaged by a
plunger or bolt D which works in a fixed guide and is operated (under the control
of a locking bar E) from a hand lever in the signal cabin directly through rod
and bell crank connections d', d, d³ the function of this bolt or plunger D being
to lock the points in whichever position they may be set. The locking bar E is
operated through the locking bolt itself which it is intended to control, and to
which it is connected by a rod e, sway lever e¹, and rod e; and the member G of
the signal detector which is operated through the locking bar, is connected thereto
through the rod F, bell crank f¹ and rod f³.
In order to render impossible the unlocking of the points, or the giving of a
conflicting signal should a connection break (between the plunger D and the
locking bar E or between the locking bar E and the rod F through which the
member G of the "detector" is actuated) when the plunger D is home, the rod F
(or a part carried thereby) is itself caused to act as a sort of plunger or bolt
detector." The rod f and plunger D cross each other at right angles and the
"detector" may be formed for example by a lug d on the plunger being timed
to coincide with and pass through a notch f in the rod f2 when the two are moved
concurrently each across the path of the other as in normal working, whereas
should the rod 2 fail to be moved in consequence of the breakage of a connection,
the rod will remain in the path of the lug d and so prevent the plunger being
withdrawn from its engagement with the stretcher C connecting the switch
tongue B.
The signal detector comprises two (or more) juxtaposed sliding members or
plates G H having as many sets of notches 1, g; 2, g; 3, g; 1, h; 2, h; 3, h; as
there are signals 1, S; 2, S; 3, S; (respectively corresponding to roads 1, 2, 3
Figure 7) to be controlled by it, a pair of notches g and constituting a set and
being adapted when the two notches of a set coincide, to give passage to the
corresponding one of three slide bars 1, I; 2, I; 3, I; each slide bar being fitted
to work in guides J and being connected to the wire 1, i: 2, i; or 3, i which is
pulled for the purpose of lowering the signal to which that set of notches and
slide bar correspond. These two notched plates or members G H have their sets
of notches preferably in the one and the other edge alternately, the adjacent
slide bars being at correspondingly different levels, so that the notches of adjacent
sets will be quite distinct in all positions of the notched plates G H.
The said notched plates are moved the one G from the plunger locking bar E.
and the other H from the stretcher C which connects the switch tongue B and
with which the locking plunger or bolt engages as above mentioned, the plate H
being connected to the stretcher C by a rod c and bracket arm c¹.
The extent of motion of the two plates G H is different and such that when the
plate G is moved by the unlocking of the switch none of its notches g will coincide
with notches h of the plate H and when the plate H is moved in turn by the
setting of the switch in another position none of its notches h will coincide with
the notches and no signal can yet be lowered. But on the switch being locked
by the plunger or bolt D in the new position in which it has been set, the notches
of that set which corresponds to a particular signal $ will coincide and give
passage to the corresponding slide bar I so as to permit of that signal being

page_text: lowered in order to denote that the points are so set, all other signals controlled
by that detector being maintained at danger.
The operation of the slides will be readily understood by an inspection of the
diagram Figure 6 in which the slides G H are represented one above the other,
it being understood that it is only when two notches (one notch of each plate)
coincide with each other and with one of the three ordinates 11 12 13 which
indicate the positions of the slide bars 1, I, 2, 1, 3, I, that movement of the corre-
sponding slide bar is permitted.
In the first position the points are supposed to have been opened for roads
Nos. 1 and 2 and are locked in that position by the plunger bolt having been
moved home. It will be seen that the notches of the sets 1g 1h, and 2 g, 2h,
coincide with the ordinates I¹ 12 consequently the one or other of the
signals 1 S, and 2 S can be lowered.
Position No. 2 shows relative position of the plates after the plate G has been
moved by the locking bar in consequence of the plunger bolt having been with-
drawn in order to unlock the switch. In this position none of the notches of the
one plate coincide with a notch of the other plate and no signal can be lowered.
Position No. 3 shows the relative position of the plates after the plate H has
been moved by the opening of the points for road No. 3. In this position also
none of the notches of the one plate coincide with a notch of the other plate and
no signal can be lowered.
Position No. 4 shows the relative position after the plate G has been returned
to its original position by the relocking of the points in the new position by the
plunger bolt. In this position the notches 3g, 3h coincide to give passage to
the slide bar 3 I, for the purpose of lowering the signal 3 S, the movement of the
others being prevented.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. In railway point locking and signal detecting apparatus the connection of
the switch locking plunger or bolt directly with the operating lever, of the
locking bar with the switch locking plunger or bolt, and of one member of the
signal detector with the locking bar, substantially in the manner described, so
that motion will be communicated from the lever to the bolt, from the bolt to the
locking bar and from the locking bar to the detector, whereby to ensure that the
setting of the signals shall be dependent on the previous setting and locking of
the points notwithstanding the breakage of an operative connection, substantially
as specified.
2. In the herein described apparatus operating as specified in Claim 1, the
combination of the locking plunger or bolt, and of the detector operating bar to
form a detector by which the one gives passage to the other only when their
movements are coordinated as described.
3. A signal detector consisting in the combination with slide bars at different
levels and moved by the signal connections of two or more juxtaposed plates having
notches at different levels adapted when the two notches of a set coincide to give
passage to the corresponding slide bar, substantially as specified.
Dated this 4th day of October 1800.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.