Improvements in Electrically Controlling the Levers of Railway Signal Interlocking Apparatus.
Year: 1892

page_text: Date of Application, 8th Apr., 1892
Complete Specification Left, 9th Jan., 1893-Accepted, 18th Feb.. 1893
PROVISIONAL SPECIFICATION.
Improvements in Electrically Controlling the Levers of Railway
Signal Interlocking Apparatus.
We LEICESTER BRADNEY STEVENS, of Darlington Works, Southwark
Bridge Road, in the County of Surrey, Engineer and WILLIAM ROBERT SYKES
of Station Road, in the County of Surrey, Telegraph Engineer do hereby declare
the nature of this invention to be as follows:-
This invention for improvements in electrically controlling the levers of railway
signal interlocking apparatus has for its object to detect the positions of railway
points and facing point locks, so that a signal lever cannot be worked unless both
Longues of the switch, and the plunger of the facing point lock are in their proper
positions for such signal to be given.
The lock which controls the signal lever is formed in such a manner that the
armature of the controlling electro-magnet itself forms the lock; and the outside
contacts are arranged at the points so that when the electric circuit is complete for
a branch signal one tongue of the switch must be home against the stock rail and
the other tongue must be open to its proper distance; also, the plunger of the
facing point lock must lie in such a position that the points are locked. When the
circuit is complete for a main signal to be lowered the various parts are similarly
actuated, the respective tongues then being in the reverse positions. A final break
is also provided in the circuit at the drop box attached to the catch handle of the
signal lever to prevent the waste of battery power when the lever is in its "danger'
position.
Dated this 8th day of April 1899
"
WHEATLEY & MACKENZIE,
40, Chancery Lane, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Electrically Controlling the Levers of Railway
Signal Interlocking Apparatus.
We LEICESTER BRADNEY STEVENS, of Darlington Works, Southwark
Bridge Road, in the County of Surrey, Engineer, and WILLIAM ROBERT SYKES,
of Station Road, High Street, Clapham in the County of Surrey, Telegraph
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 for improvements in electrically controlling the levers of railway
signal interlocking apparatus has for its object to detect the position of railway
points and facing point locks, so that a signal lever cannot be worked unless both
tongues of the switch and the plunger of the facing point lock are in their proper
positions for such signal to be given: and consists in forming the lock, which con-
trols the signal lever, in such a manner that the armature of a controlling electro-
magnet itself forms the lock; and in arranging the outside contacts at the points
so that, when the electric circuit is complete for a main or branch signal, one tongue
of the switch must be home against the stock rail, and the other tongue must be
open to its proper distance, also, the plunger of the facing point lock must lie i
such a position that the points are locked, a final break being provided in the
TD 077

page_text: UL the signal lever to prevent the waste of battery
power when the lever is in its "danger" position.
In the accompanying three sheets of illustrative drawings:-
Figure 1 is a plan and Figure 2 an elevation of one form of electric contact
apparatus constructed according to this invention.
Figure 3 is an elevation of the electric signal lever locking device.
Figure 4 is a perspective view indicating diagramatically a modified arrangement
of contact apparatus and
Figures 5 and 6 are sectional elevation and plan respectively of a further
modified arrangement of contact apparatus.
Referring to Figures 1, 2 and 3 of the drawings; two parallel bars a, b sliding
on, but independently of, one another and in the frame c have each one end con-
nected directly, or by a suitable link, to a corresponding tongue of a switch so
that as the said tongues are operated a corresponding longitudinal motion is
imparted to the sliding bars. To the bar a is attached by a plate d an insulated
contact plate e, while to the bar bis similarly attached, by the plate f, a similar
insulated contact plate g. The plates e, g. are electrically connected by the
conducting wire hand operate in conjunction with the contact pieces i, l, m, n
symmetrically and parallelly arranged and mounted on the insulating plates o
secured to the frame c. It will be seen that so long as the switch tongues to which
the bars a, b are respectively connected are in proper working order and move
parallel to one another the two bars a, b slide together as one, with no motion
relatively to one another; but should the relative positions of the tongues become
changed, as by the breaking of a stretcher bar, the bars a, b slide on one another,
and the contact plates eg fail to preserve the relative positions necessary to compléte
the electric circuit.
A spindle p sliding in guides q has secured to it a stop sleever with a flange or
cross pieces to prevent its turning, a stud t of insulating material secured to it
being forced by the spring against the contact spring to so as to normally break
the contact between it and the contact piece x. On sliding the spindle forward
against the pressure of the spring contact between the spring w and piece is
re-established as will be readily understood. The contact pieces 1, m are electrically
connected with the lock controlling devices of the main and branch signal levers
respectively, while the contact piece r is connected to an electric battery. The
apparatus is so placed with respect to the facing point lock mechanism, that when
the plunger is forced home in the plunger stretcher bars its end strikes the end
of the spindle p and slides it forward against the force of the spring which allows
the contact w to close.
66
=
Each signal lever y is provided with a drop box containing the lever locking
device. Normally, with the signal at danger," the hinged armature aa of an
electromagnet ab falls by gravity into engagement with the recessed tail ac of the
arm a secured to the signal lever y thereby securely locking it. The terminal a e
or af is connected to one of the contact pieces 1, n while the other terminal is con-
nected to the battery, or to earth, as the case may be.
When the switch is in working order, and the points correctly set for a given
traffic movement, the contact plates e. a make contact with the pieces i, I as shown
and the contact wo, Figure 1, is closed as before described. On raising the catch
handle of the appropriate signal lever y a stud ag raises the lever ah causing the
roller ai, of insulating material, to displace the plate al and to close the contact a m
and to finally complete the electric circuit through the battery B, contacts wo,
plate w, bracket an, contact piece, plate e, conductor h, plate g, contact piece l,
conductor a o, and electro-magnet ab back to the battery thereby energizing the
magnet ab which attracts its armature aa, thus removing the lock from the signal
lever.
The setting of the switch for the alternate route shifts the contact plates e, g on
to the contact pieces m, n and enables the electric circuit to be closed and the lock

page_text: to be removed on operating the appropriate signal lever in a similar manner to that
already described as will be readily understood. Where several switches have to
be set for a given route a contact apparatus is fixed at each switch, and all are
arranged so as to be in one electric circuit, so that unless all the points in the
route are properly set the raising of the catch handle of the appropriate signal
lever does not close the electric circuit to remove the lock.
+
In the arrangement illustrated in Figure 4 the sliding bars a, b and plates eg in
Figures 1 and 2 are replaced by a single bar ap and plate ag connected to the
switch tongues ar, as by the rods a t, a v and sway lever a wo. In this case the con-
tact pieces are arranged in a straight line, the plate a q connecting the battery to
the fever line direct instead of through the two plates e, g and conductor h in
Figures 1 and 2. The method for closing final contact in this modified arrange-
ment by means of the point locking plunger is similar to that shown in Figure 1
and will be readily understood from the drawings.
In the modified arrangement shown in Figures 5 and 6, insulated contact
plates aa ay are connected by the bars az ba, to the tongues bb bc of the switch.
When the points are in their proper position for a traffic movement the end of the
point lock plunger passes beneath the insulated projection bd on the contact
spring be and closes the contact bf. The current then passes through the spring be,
insulated plate of through plates bg, bh, spring a a, plate bi, spring a y, and one or
the other of the plates b1, bm, to the appropriate signal lever.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is
1. In apparatus for electrically controlling the levers of railway signals:
automatically locking the signal lever in its "danger" position so that it cannot be
operated unless both tongues of the switch and the facing point lock plunger
occupy their proper positions for the required signal to be given substantially in
the manner described in the foregoing Specification and illustrated in the annexed
drawings.
2. In detector contact apparatus for electrically controlling the levers of railway
signals: the employment of two independent sliding bars separately connected to
the two corresponding tongues of the switch and carrying insulated contact plates
electrically connected together and working in conjunction with contacts connected
respectively to an electric battery and to the corresponding signal lever locking
device, substantially as described and for the purpose specified.
3. In the electric detector contact apparatus referred to in Claim 2: completing
the electric connection between the battery and the sliding bar contact by means of
the facing point lock plunger operating so as to close a final break in the connection
substantially as described.
4. In detector contact apparatus for electrically controlling the levers of railway
signals: the sliding bars a, b, insulated contact blades e, g, and contact
pieces i, l, m, n, contact plate w and contact piece .r, in combination with the sliding
spindle p carrying a stud t and operated by the facing point lock plunger, substan-
tially as described.
5. The arrangement construction, and combination of parts, constituting our
improvements in electrically controlling the levers of railway signal interlocking
apparatus substantially as described with reference to Figures 1, 2, and 3 of the
annexed drawings.
6. In detector contact apparatus for electrically controlling the levers of railway
signals; the employment of a single sliding contact bar, carrying an insulated
contact plate acting in conjunction with contact pieces connected to the battery
and signal lever locking device, the said bar being connected to the tongues of
the switch and operated substantially as described with reference to Figure 4 of
the drawings.

page_text: 7. The arrangement and construction of detector contact apparatus for
electrically controlling the levers of railway signals, substantially as described with
reference to Figures 5 and 6 of the annexed drawings.
Dated this 9th day of January 1893.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.