Improvements in Block Signal Apparatus.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Block Signal Apparatus.
I THOMAS HENRY PATENALL of Rahway in the County of Union, in the
State of New Jersey, United States of America, Signal 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:—
My invention relates to improvements in block signal apparatus for controlling
the movements of trains along a railway route.
While my present apparatus embodies some of the generic features of what is
commonly known as the Sykes block signal system, it differs fundamentally there-
from in this, that while, in the Sykes system, the signal operating levers are locked
in both the positions of "line blocked" and "line clear," my present apparatus
provides for locking the signal-operating mechanism in the position of "line
blocked" only, leaving it, when in the position of "line clear," free to be manipu-
lated, to throw the signal either to "danger" or "safety," as may be desired, while
at the same time I provide means for preventing plunging to a preceding station a
second time, until the train shall actually have passed out of the block and into
the next succeeding block. My invention further contemplates a normally twice-
broken plunger circuit, requiring an intentional setting of an instrument at any
station before it can be successfully plunged to by the next succeeding station,
means for shifting the closed plunger circuit to the closed treadle circuit, and
the simultaneous breaking of the plunger circuit; means for regulating the move-
ment of the plunger and indicator in connection therewith; and in various details
of structure and arrangements of parts.
For the purpose of illustrating my invention, I have shown a diagrammatical
representation of three successive towers or sections along a double track railway,
indicating the signals, track treadles, and the electric connections and circuits. I
have also shown one of the several instruments employed for the purpose of locking
and releasing the signal operating mechanism, and it is to be understood that two
such instruments are to be employed at each station or tower, one or more for each
track.
In the accompanying drawings
--
Fig. 1 represents a vertical sectional view, from front to rear, of one of the
instruments, showing the operating parts therein in side elevation.
Fig. 2 is a horizontal section through the instrument, showing the operative parts
therein in top plan.
Figs. 3 and 4 are detail views of the plunger and mechanism under its
immediate control, showing, in Fig. 3, the position of the parts when the plunger
has reached the limit of its inward movement, and, in Fig. 4, the position of
the parts when it has been withdrawn.
Fig. 5 is a front view of the indicator.
Figs. 6 and 7 are views, in detail, of the indicating plates.
Fig. 8 shows the connection of the instruments with the locking mechanism for
locking and releasing the signal-operating levers; and
Fig. 9 is a diagrammatical illustration of three successive towers or stations
along a double track.
I will first describe the structure and operation of the several parts comprising,
one of the instruments, and will then describe the practical operation of a series of
such instruments, by referring to the diagrammatic Figure 9, and assuming that
each of the stations there noted is provided with two instruments similar to the one
which I shall particularly describe.
The casing of the instrument is represented by A, and it may be of oblong

page_text: rectangular form as herein shown, or any other form which may be found desirable.
Within the casing A, there is mounted a longitudinally sliding bar B, which
projects, at its front end, through the casing, and is there provided with a section B¹
hinged to the section B, as at b, and provided with an operating handle b. The
section B' is also provided with a downwardly extending lip 62, adapted to engage
the abutments a and a' on the bracket A', projecting from the front of the casing A,
and thereby hold the bar B in the desired longitudinal adjustment. The bar B is
further provided with an elongated notch, and a shorter notch 64 located at its
upper edge.
An angle plate C is pivotally secured to a support at the bottom of the
casing, and has its upwardly-extending arm or portion provided with a bearing c
for the reception of a stud 66 on the side of the bar B, to rock the plate in
the direction to lift the operating rod C¹ secured to the horizontal arm of the
rock plate C. The upper portion of the plate C is further provided with a
bearing shoe el, along which the stud is adapted to move, as the bar B is slid, so
as to admit of a predetermined longitudinal movement of the said bar B, before it
effects a rocking of the plate C, while at the same time the movement of the bar B
in the opposite direction, will tend to rock the plate C in the direction to return it
to its normal position with the rod C¹ depressed.
The rod C extends downwardly, and connects with a slide for locking and
releasing the signal operating levers in any well known or approved manner.
In
the present instance, the elevating of the rod C₁ serves to unlock the signal
operating levers, while its depression serves to lock them.
The bar B is allowed at all times, save when it is at the limit of its outward
thrust, a longitudinal sliding movement, corresponding to the length of the recess 6³.
Such movement is sufficient to place the lip 2 in position between the abutments a
and a. Beyond this, the bar cannot be slid until it is unlocked by the lifting
of the latch d, secured to the end of a vibrating lever D, pivoted to a suitable
support, as at , and carrying the armature of an electro-magnet E. The
latch is a gravity latch, and rests in contact with the bar B, whenever it is not
positively held out of engagement therewith, either under the influence of the
energized magnet E, or a catch d³. The catch d³ depends from a lever de pivotally
secured at d, and counterbalanced by a weight d. The forwardly-extending arm
of the lever is connected by a rod d' with an arm d8 on the rock shaft F,
mounted in the upper portion of the casing, and having secured to its forward end
an indicator plate f. The rock shaft F is provided with a counterbalance weight f",
to counterbalance the weight of the indicator plate f, and leave the shaft F
free to be rocked by the movement of the lever d', through the connecting
rod d.
The counterbalancing of the lever d' and rock shaft F is so arranged, that
the forwardly-extending arm of the lever d tends normally to fall under the
influence of gravity, and thereby swing the catch d³ to the right. If the lever D
be lifted by the attraction of the magnet E, the catch d' will take under the end
of the lever D, and hold the latch d out of engagement with the bar B, until the
lever has been positively rocked in a direction to release the catch d³. Such
positive movement of the lever d' is effected by an upwardly-extended cam G,
fixed to the bar B, and adapted to engage an antifriction roller & mounted in
bearings depending from the under side of the lever d', as the bar B is slid back
and forth.
A vertically sliding bar H is held in position within the casing by bearings h
and h¹, and is connected with the horizontally sliding bar B, so as to fall as the
bar B is pulled out, and rise as the bar is pushed in. I have shown the connection
between the bars B and H as consisting of arms 2 and 3 fixed to and radiating
from a common rock shaft h, and provided at their free ends with elongated open-
ended slots h and h, adapted to receive studs, the one, 66, extending from the side
of the bar B, and the other, b', extending from the side of the vertically-sliding
bar H.

page_text: A vibrating arm I is pivotally secured, as at i, to a support within the casing,
and has a loose connection, in the present instance a slot and pin connection, at,
with the vertically-sliding bar H, and at its opposite end it carries a pair of
circuit-making jaws and i, insulated from the arm I, but electrically connected
with each other by one or both of the fastening screws i*.
Three contact plates K, K', K2 are normally insulated from each other, and
secured to the interior of the casing, so that as the sliding bar H is lowered, and
the jaws and thereby elevated, the latter will simultaneously come in contact,
the one with the plate K³, and the other with the plate K, and thereby bring the
two plates into electric communication with each other. The arrangement is such,
that as the bar H further descends, it will swing the jaws and past the plate K³,
and bring them into simultaneous communication, the one with the plate K', and
the other with the plate K, and thereby establish electrical communication between
the plates K and K, and break communication between the plates K' and K.
In the present instance, I have shown the plate K separated from the two plates K¹
and K by an intervening layer, k, of insulated material, and the plates K and K'
occupying positions on the opposite side of the layer of insulating material from the
plate K, and separated from each other by a strip of insulating material k¹. The
plate K2 is in normal electrical communication with the line wire S' (see Fig. 9,
Station 3, instrument R); the plate K' is in permanent electrical communication
with the treadle T; and the plate K is in permanent electrical communication with
the electro-magnet E, for purposes which will hereinafter appear.
The vertically sliding bar H carries, on its side, a vibrating arm L, located in
the path of the plunger M, and provided with a spring 1, the tension of which
tends to keep the arm normally swung toward the plunger. The arm L is provided
with a block of insulating material, the nose of which is in position to engage a
flexible electrical conducting strip N, depending from a suitable support within the
casing, and carrying a contact pin n, adapted to be thrown into and out of contact
with an electrical conducting strip 0, uprising from the lower portion of the casing.
The strip N is in permanent electrical communication with the line wire S, and the
strip O with a battery z, and through it with a wire s, leading to the electro-magnet
of the preceding instrument (see Fig. 9).
The plunger M is housed by a barrel a², fixed to the front of the casing, and is
provided with an actuating spring m, the tendency of which is to throw the plunger
outward to the limit of its movement. Within the casing, and in the path of the
plunger, there is located a drop plate P, carrying, at its upper end, an indicator p,
shown in detail in Fig. 7. The drop plate P'is provided with a movable section pl,
so attached to its inner face, as to drop a predetermined distance independently of
the plate P. The section p¹ is provided with an inwardly extending nose p', adapted
to interlock with a corresponding nose on the arm L. The plate P is provided
with an opening therethrough, sufficiently large to give the plunger a clearance
therein, but not elongated or enlarged sufficiently to admit of the plate P dropping
when the plunger is inserted through the plate, sufficient to bring the indicator p
into position to show "train on." The moveable section p¹ is provided with an
opening therethrough, which normally registers with the opening p³ in the
plate P, but which is sufficiently elongated to allow the section p' to drop, when
the plunger is inserted, a distance sufficient to allow the nose p³ to move down-
wardly past the nose on the arm L, as indicated in Fig. 3. When the section pl
has reached the position shown in Fig. 3, the withdrawal of the plunger will
permit the arm L to swing toward the front, and will carry its nose above the
nose on the section p', and thereby permit the drop plate P, and its movable
section p', to drop to the limit of their downward movement, to bring the
indicator p into position to show "train on." If the plunger be only partially
withdrawn, so that it still remains, to some extent, within the opening p³, the
section will drop far enough past the opening p³, to prevent the plunger from
being again pushed in, into contact with the arm L, until the drop plate has been
elevated to its normal position. The drop plate and its movable section are held

page_text: normally in their elevated adjustment by the engagement of the nose of the
arm L under the nose p² of the section p³, and after the said drop plate has been
once lowered, it can only be raised by the subsequent lowering of the bar H under
the impulse of the sliding bar B, so as to carry the nose 1, on the arm L, down-
wardly underneath the dropped position of the drop plate P. For the purpose of
allowing the nose to ride past the nose p', and for the further purpose of enabling
the return forward movement of the arm L to exert a downward pressure upon
the movable section p², I provide the upper side of the nose p³ with bevelled
faces and respectively.
The indicators and p occupy positions behind an opening a³ in the casing,
through which they may be seen. The opening is conveniently covered by a glass
plate at at the front, and at the rear by an opaque plate a³, provided with slots a³
and a', through which the indicating words or symbols may be read, when the
operating mechanism has been moved into the proper position to bring such
indicating words into position.
For the purpose of utilizing a single line wire for connecting the instruments
for moving the train on both the in-coming and out-going tracks, I provide a
connecting strip Q in permanent electric connection with the contact plate K'
of the companion instrument at any station (see Fig. 9), and normally connected
with the line wire leading to the adjacent station, by means of a connecting
arm carried by the depending strip N. When the strip N is swung inwardly,
under the impulse of the plunger, the aring will be disengaged from the strip Q,
and the circuit through the companion instrument broken, while the circuit
through the electro magnet at the next preceding station is closed.
In the diagrammatic illustration (Fig. 9), I have denoted the stations, from
left to right, as Station One, Station Two, Station Three; the incoming and
outgoing tracks are indicated by arrows. The treadles in connection with the
incoming track are denoted by T, and in connection with the outgoing track
by T
The instruments. for moving the trains along the outgoing track are
represented by R', and those for moving the trains along the incoming track
by R. The electro-magnets of the instrument R are denoted by E, and those
of the instruments R₁ by E'. The contact strips of the instruments R are
denoted by N, O, and Q, and of the instruments R₁ by N¹, O', and Q.
It is to he understood that the several instruments R and R' are similar to
that which had been hereinabove particularly described, and their practical
operation will now be set forth by referring to the several parts of the different
instruments.conveniently indicated in the diagrammatic Fig. 9 by the same letters
which have been used to indicate those parts in the one instrument which has
been described.
66
Suppose a train to be on the outgoing track, and moving from Station One
toward Station Two. The operator at Station Two, before he can place his
signal at safety," to allow the train to pass toward Station Three, must have
his sliding bar B unlocked by the operator at Station Three, so that he, viz.
the operator at Station Two, may draw his bar B outward to its full extent,
and thereby unlock his signal-operating levers. Furthermore, before the operator
at Station Two can have his instrument unlocked by the operator at Station Three,
it is necessary for him (the operator at Station Two) to slide his bar B of
instrument R outwardly the distance permitted by the recess ³ in its upper
edge, which will enable the lip 2upou the swinging section B₁, to drop between
the abutments a and a', and will lower the bar H, and thereby lift the jaws
and into contact with the plates K and K, thereby placing the electric circuit,
through the electro-magnet E' of his instrument R₁, in condition to be closed
by the inward thrust of the plunger of the instrument R' at Station Three. By
following the diagrammatic Figure 9, it will be observed, that this circuit is
complete through the contact strips N and Q of the instrument R at Station Two,
through the line wire S', and the track wires of the strips N' and O' of the
instrument R', at Station Three.

page_text: The operator at Station Two, having been plunged to by the operator at
Station Three, and his sliding bar B having been unlocked by the energizing of
the electro-magnet E' at Station Two, and the consequent lifting of the latch d
out of engagement with the bar B, the latter will remain held out of contact with
the bar B by the engagement of the catch d³ with the end of the lever D. The
swinging of the lever d' will, at the same time, through the connecting rod ď and
the rock shaft F, drop the indicator f into position to read "unlocked."
The operator at Station Two may now draw the bar B outwardly to its full
extent, so as to lift the connecting rod C', and thereby unlock the signal-operating
levers. As the bar B is drawn outwardly to unlock the signal operating levers,
the cam G engages the roller d' depending from the lever d', and rocks it, so as to
momentarily release the catch ds from the end of the lever D, and allow the latch d
to again drop into engagement with the bar B, so that when the latter reaches its
outward limit, the latch will engage the notch 6 in the bar B, and lock it in its
outwardly drawn position, until the electro magnet E' of the instrument R' at said
Station Two, shall again be energized to release the latch.
The outward movement of the bar B, to unlock the signal-operating levers, will
further depress the bar H, and thereby swing the jaws and, from their position
in contact with the plates K K³, into contact with the plates K K', and, by so
doing, will break the plunging circuit, and place the track treadle circuit in
condition to be closed by the passing train.
The energizing of the electro magnet E¹, to unlock the lever B, will take place
only when the train has passed Station Two, and, by so doing, has operated the
track treadle T' at said Station Two, and thereby closed the circuit through the
contact plates K K', and the wires leading thence, the one directly to the treadle,
and the other through the electro magnet to the battery, and thence to the treadle.
The signal operating mechanism is independent, in a broad sense, of the lock-
controlling mechanism, and from this it follows, that :-
:-
While the bar B remains locked in its outwardly drawn adjustment, the signal
operating levers may be manipulated to set the signal at "safety" or "danger" at
pleasure, and the switch operating levers, which, by a well known mechanism, are
commonly interlocked with the signal operating levers may be manipulated to shunt
trains.
While the operator at Station Two may change his signals and switch, at
pleasure, to control the train approaching his station from Station One, he cannot
plunge to Station One, so as to unlock the instrument at Station One, and thereby
allow the operator at that station, to pass another train on to the block between
Stations One and Two, until the train, which has been assumed as approaching
Station Two, has actually passed that station, and, by its action upon the track
treadle T at that station, released the bar B, and thereby permitted the bar B to
be thrust inward, and the plunger thereby left free to be operated.
The inward thrust of the bar B brings the cam G again into engagement with
the roller d', and thereby rocks the catch d³, and permits the lever D to drop, and
thereby lock the bar B, and also elevates the indicator plates to their normal
positions shown in Fig. 1.
The locking of the plunger in the instrument R' at Station Two, is assumed to
have taken place before the operator at that station asked to be released by the
operator at Station Three, and in the following manner :- When the operator at
Station One asked the operator at Station Two to unlock his instrument in the
same manner as the operator at Station Two asked the operator at Station Three
to unlock his instrument, as hereinabove referred to, the operator at Station Two
plunged to the operator at Station One, and in so doing, swung the arm L out of
engagement with the drop plate P and its section p', and allowed the said plates to
drop and thereby shut off any possible second inward thrust of the plunger M,
until the bar H had been lowered by the full outward movement of the bar B, and
the subsequent inward thrust of the bar B, and the consequent raising of the bar H,
and with it the drop plate P.

page_text: As has been already described, the inward thrust of the bar B can only take
place after it has been unlocked by the passage of the train over the treadle at
that station, and hence there can be no plunging from the Station Two, to accept
another train, until the train already on has actually passed that station.
The same operation as described with reference to Station Two, will take place
at Station Three, and each succeeding station along the line, and similar operations
will take place in the instruments R at Stations Three, Two, and One, and each
succeeding station in that direction, in the movement of trains on the incoming
track.
In referring to track treadles and track treadle circuits in the foregoing
description, it is to be understood that what is commonly known as "the track
circuit," as distinguished from the track treadle, might be employed.
In using the word "independent," to distinguish the relation between the lock-
controlling and signal-operating mechanisms, I have employed it in the broad sense
of independent, so far as operation is concerned.
It is obvious that changes might be resorted to in the construction and arrange-
ment of the several parts described, without departing from the spirit and scope of
my invention; hence I do not wish to limit myself strictly to the construction and
arrangement herein described.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what L
claim is :-
1. The combination with signal operating mechanism, and means for locking and
releasing it independent of the signal operating mechanism, of means for controlling
the unlocking of said mechanism from a remote point along the line, and means for
coutrolling the locking of said mechanism from another remote point along the
line, the said signal-operating mechanism, when once unlocked, being free to be
repeatedly manipulated to denote "safety" or "danger," at pleasure, until again
locked, substantially as set forth.
2. The combination with a plurality of signal-operating mechanisms, of instruments
for controlling the locking and unlocking of said operating mechanisms, one of the
instruments being under the control of a succeeding instrument; to unlock it, and
hence the signal-operating mechanism connected therewith, and under the control
of the passing train, to permit the locking of the said signal-operating mechanism,
and a movable stop under the control of the locking mechanism, for preventing the
unlocking of a preceding instrument while the signal-operating mechanism at the
succeeding instrument remains unlocked, substantially as set forth.
3. The combination of a sliding bar under the control of the operator, a movable
part under the control of the sliding bar, and means for locking and releasing the
signal-operating mechanism, also under the control of the sliding bar; of a latch for
locking and releasing the sliding bar; means for operating the latch; a plunger;
an electric circuit adapted to be closed by the plunger, to unlock a remote
instrument, and a plunger-locking device under the control of the aforesaid movable
part, to prevent the second operation of the plunger, until the said sliding bar is
returned to its normal position, substantially as set forth.
4. The combination with the signal locking and releasing mechanism, of the
normally twice-broken electric circuit, for plunging to a preceding station, and
means for positively closing said circuit at the station to be plunged to, for securing
a release of the signal-locking mechanism, substantially as set forth.
5. The combination with the signal locking and releasing mechanism, of the
normally twice-broken electric plunging and track treadle circuits, a circuit closer,
and means for moving the circuit closer successively into position, to close the
plunging circuit, and then in position to break the plunging circuit, and close the
track treadle circuit, substantially as set forth.
6. The combination with the bar for mechanically unlocking and locking the
signal-operating mechanism, of a gravity latch for locking the said bar in position

page_text: to lock the signal operating mechanism, and in position to release the signal-
operating mechanism, and an electro-magnet for releasing the latch, the said
latch being under the control of the said bar, to allow it to fall into engagement
with the bar, substantially as set forth.
7. The combination with the bar for unlocking and locking the signal operating
mechanism of a gravity latch for locking said bar in its positions to lock and
unlock the signal operating mechanism, an electro magnet for withdrawing the
latch, and an indicator under the control of the latch, to indicate "locked" or
"unlocked," the said latch being under the control of the said bar, to allow it
to fall into engagement with the bar, substantially as set forth.
8. The combination with the plunger and the plunger electric circuit, of the
drop plate through which the plunger passes to plunge, and the movable section
on the drop plate, the latter having a sliding movement independently of the
drop plate, in a direction transverse to the plunger, substantially as set forth.
9. The combination with the plunger, the electric plunger circuit, and the
swinging contact piece provided with a nose, of a drop plate through which the
plunger passes to plunge, and a movable section carried by the drop plate, and
provided with a nose adapted to interlock with the nose on the contact piece,
the said movable piece having an extended dropping movement while the plunger
is thrust in to carry its nose past the nose on the contact piece, substantially
as set forth.
10. The combination with separate instruments at a station for controlling the
movements of trains in opposite directions, of electric plunging circuits, one in
connection with each instrument, each circuit comprising a portion of the plunger-
actuated circuit-closing mechanism of the other instrument, to complete the
plunging circuit through its own electro-magnet, substantially as set forth.
11. The combination with the means for connecting the sliding bar with the
device for unlocking and locking the signal-operating levers, of the sliding bar
having a predetermined movement relatively to said connecting means, without
effecting the unlocking or locking, the latch for locking the bar, and at the
same time permitting said predetermined movement, the circuit closer under the
control of the said bar, and the normally twice-broken electric circuit adapted
to be closed, as to one of the breaks, by said circuit closer, substantially as set
forth.
Dated this 4th day of August 1892.
NEWTON & SON,
Agents for the Applicant.