IMPROVEMENTS IN SELF ACTING BLOCK SIGNALLING APPARATUS
Year: 1882

page_text: LETTERS PATENT to Eugène Callot, Agent-voyer de la Ville de St. Denis
(Seine), 3, cours Chavegny, St. Denis, for an invention of "IMPROVEMENTS IN
SELF ACTING BLOCK SIGNALLING APPARATUS.”
PROVISIONAL SPECIFICATION left by the said Eugène Callot at the
Office of the Commissioners of Patents on the 6th March 1882.
EUGÈNE CALLOT, Agent-voyer de la Ville de St. Denis (Seine) 3 cours Chavegny
St. Denis "IMPROVEMENTS IN SELF ACTING BLOCK SIGNALLING APPARATUS.
The object of this invention is to produce an apparatus which shall effect the
automatic putting on and taking off of the optical discs or signal arms usually
employed on railways, in such manner that every train passing over an apparatus
of this kind sets behind itself an optical signal placed at the preceding apparatus,
which signal shows "danger" or blocks the next following train until the first one
has passed over the next apparatus.
By means also of this apparatus each train places on the line at a certain distance
behind it explosive signals which warn the persons in charge of the next train if
from any cause the optical signal has been disregarded.
The general arrangement is as follows,
When a railway train passes over the first apparatus a pedal in the latter is
pressed down, is held in a given position and the signal arranged at the departure
station is put on (enigestellt). When the train passes the second apparatus its
pedal is likewise pressed down, and the signals placed at the first apparatus (the
optical and the explosive signals) are brought into the position for covering the said
train, whilst the first mentioned signals are taken off. (Abgestellten). At the
passage of the third apparatus the pressure on its pedals takes of the signals at the
first apparatus and puts on those at the second. Thus each train always leaves
behind it an optical and an explosive signal at a certain minimum distance
according to circumstances, and a train following the first one cannot enter the
covered zone without the aforesaid signals informing the persons in charge of such
train of the prescence of a preceding train.

page_text: CONSTRUCTION OF THE APPARATUS.
The apparatuses combined with each other are of exactly similar construction.
A double pedal is arranged to turn on centres and is so placed that its arms run
parallel to and by the side of the rails, but do not project above the level thereof;
at the point where they reach to the level of the rails are fixed two converging bars
connected together by a cross piece; at the same point on these arms are also fixed
downwardly inclined prolongations. These prolongations guard the apparatus from
injury in case a train should by reason of an accident or otherwise move in any
other than the prearranged direction; in this case the train moving in the wrong
direction puts on the safety signal in the front of it, and thus prevents a collision
with a train moving in the opposite direction.
The free end of the pedal is constantly pressed upwards by flat springs which
are connected together at their points of fixture by two encompassing plates. In
order to reduce as much as possible the friction of the free movable ends of the
springs on the pedal when the latter is pressed down they are connected together
by a cross piece which carries at its ends friction rollers which alone come in direct
contact with the pedal and receive the pressure, transmitting it to the aforesaid
springs. By these means the sliding friction of the springs is transformed into the
lesser rolling friction.
The cross bar connecting the converging bars carries an angle piece strengthened
by vertical ribs, between which are carried three rollers one of which for convenience
in the following description may be designated the primary roller and the other
two, secondary rollers. This cross bar also carries a fork in which is carried a
fourth roller. Two other rollers carried in fixed bearings below the free ends of
the pedal serve in combination with the said fourth roller to guide a chain, which
is fastened to a traction wire connected with the signal devices at the preceding
apparatus. This chain is fixed at one end and is drawn in or let out by the
movement of the pedal.
If the pedal is pressed down by the flanges of a pair of wheels rolling over
the apparatus a latch which may be called the primary latch takes over the
primary roller and holds the pedal in the depressed position till further action is
required.
A prolongation upwards of the primary latch lays against its corresponding
primary roller whilst two other latches which may be called secondary latches take
an inclined position free of the secondary rollers. Springs press against these three
latches and preserve their relative positions when the apparatus is at rest. The
primary latch is so connected with a drum by a small chain or wire passing over
it that by turning the said drum to the right hand for example the said small chain
or wire is tightened and the resistance of the spring acting on the primary latch is
overcome.
The two secondary latches are each connected with the said drums by means of
a chain or wire passing under the same so that these latter chains or wires become
slack when that connected to the primary latch is tightened and vice versa.
The aforesaid drum receives its motion from a lever to which the traction wine
connected with the moving mechanism of the signal device at this apparatus is
joined.
There are thus present in connection with each apparatus two ends of traction
wires. One goes from the apparatus to join on to the traction wire, which leads
towards and is connected with the signal device at the preceding apparatus after
which it joins the corresponding drum lever in that apparatus. The other joins on
to a moveable bar carrying the explosive signal.
The action of the apparatuses on each other is as follows:-
In order to render the action clear it will be necessary to consider at least three
such apparatuses placed behind one another, over each of which in succession a
railway train is supposed to pass. These three apparatuses will be numbered
respectively I. II, and III,

page_text: It should here be understood that an apparatus and the signal preceding it are
to be always regarded as, in a sense, belonging to each other."
When the trains roll over the apparatus No I the pedal in that apparatus is
pressed down and is held fast by its primary latch taking over its primary roller.
By the simultaneous depression of the chain roller on the pedal the chain and the
traction wine fastened there-to are slackened and a compensating-weight connected
with it is lowered drawing after it the traction wire leading to the signal device
belonging to apparatus or station preceding No I. This movement is transmitted
in the usual way to the optical and explosive signals. As regards the latter in
such a manner that the explosive cartridge resting on the upward bent end of a
bar which is held at the side of the track when out of action by a counterweight,
is pushed on to the rail and is thus presented to receive the pressure of the
wheel
When the train passes the apparatus No II the pedal in that apparatus is pressed
down and is held fast by its primary latch. By the simultaneous depression of the
chain roller with the pedal its chain and traction wire are slackened, a corresponding
compensating weight is lowered, and draws with it the traction wire leading to the
signal device belonging to apparatus No. II. (placed beside the apparatus No I).
By the movement of the bar, on the upward curved end of which the explosive
cartridge rests the chain or traction wire, connected to the lever of the first
apparatus is pulled and the said lever turned say to the right; this turns the drum
in that apparatus also to the right, whereby the primary latch is withdrawn from
its primary roller so that the latter, again takes its inclined position of rest.
It will be understood that the primary latch in apparatus No I. is now in a
position, in which it could not lay hold of and hold fast its pedal on the passage of
a second train over the said apparatus No I. In order to avoid this eventuality the
other or secondary latches are connected with the drum by chains which are
slackened when the primary latch is drawn back by the drum and vice versa.
In the foregoing case the said secondary latches influenced by their springs,
would take over the secondary rollers and thus hold fast the pedal in apparatus
No I when a second train passes over it.
When the pedal in apparatus No I returns again to its inclined position of rest
its chain roller pulls the chain and whereby the traction wire leading towards the
compensation weight, which is raised and thereby the traction wire leading to the
signal bar in the preceding apparatus is ceded to the action of its corresponding
counterweight, this latter draws the explosive signal, the optical signal and the
said traction wire after it and places the whole apparatus in the position of
rest.
When the first considered train passes over No III apparatus, its pedal is pressed
down and actions of the parts take place substantially the same as those at
apparatus No II. The signal devices belonging to apparatus No III (which are
placed at apparatus No 11) are put on and those belonging to No II (which are
placed at apparatus No I are taken off. By the taking off of the signal apparatus
belonging to No II the chain of the primary latch in apparatus No I is again
slackened and by the action of its spring (which must be stronger than the two
springs of the secondary latches together) the drum is turned to to the left whereby
the lever is raised and the secondary latches are drawn into the position in which
they cannot take over their corresponding secondary rollers if the pedal in No I
apparatus is pressed down.
The apparatus No I is thus restored to its original position of rest and its
primary latch returned into the position in which it can hold its pedal, when the
latter is again pressed down.
The chief parts of the moving mechanism are placed in a covered case to protect
them from the weather and dust and in order to protect the pedal springs a plate
is or may be screwed over the converging bars of the pedal so as to cover the said
springs.

page_text: the
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Eugène Callot in the Great Seal Patent Office
6th September 1882.
on
EUGÈNE CALLOT voye de la Ville de St. Denis (Seine) 3 cours Chevegny
St. Denis. "IMPROVEMENTS IN SELF ACTING BLOCK SIGNALLING APPARATUS
"
The object of this invention is to produce an apparatus which shall effect the
automatic putting on and taking off of the optical discs or signal arms usually
employed on railways, in such manner that every train passing over an apparatus
of this kind sets behind itself an optical signal placed at the preceding apparatus,
which signal shows "danger" or blocks the next following train until the first one
has passed over the next apparatus.
By means also of this apparatus each train places on the line at a certain
distance behind it explosive signals which warn the persons in charge of the next
train if from any cause the optical signal has been disregarded.
The general arrangement is as follows:-
==
When a railway train passes over the first apparatus a pedal in the latter is
pressed down, is held in a given position and the signal arranged at the departure
station is put on (enigestellt). When the train passes the second apparatus its
pedal is likewise pressed down, and the signals placed at the first apparatus (the
optical and the explosive signals) are brought into the position for covering the
said train, whilst the first mentioned signals are taken off (Abgestellt). At the
passage of the third apparatus the pressure on its pedal takes off the signals at the
first apparatus and puts on those at the second. Thus each train always leaves
behind it an optical and an explosive signal at a certain minimum distance
according to circumstances, and a train following the first one cannot enter the
covered zone without the aforesaid signals informing the persons in charge of such
train of the presence of a preceding train.
CONSTRUCTION OF APPARATUS.
The apparatuses combined with each other are of exactly similar construction.
In the drawings Fig 1 is a plan, Fig 2 a longitudinal section, Fig 2* a continuation
to the left of fig 2, Fig 3 a partial cross section and Fig 4 a partial plan to a some-
what larger scale of one of the said apparatuses. A double pedal A is arranged to
turn on centres at B, and is so placed that its arms run parallel to and by the side
of the rails but do not project above the level thereof, at the point C where they
reach to the level of the rails are fixed two converging bars 1 connected together
by a cross piece E; at the same point C on these arms are also fixed downwardly
inclined prolongations F. These prolongations guard the apparatus from injury in
case a train should by reason of an accident or otherwise move in any other than
the prearranged direction; in this case the train moving in the wrong direction
puts on the safety signal in front of it, and thus prevents a collision with a train
moving in the opposite direction.
The free end of the pedal is constantly pressed upwards by flat springs G
which are connected together at their points of fixture by two encompassing
plates H.
In order to reduce as much as possible the friction of the free moveable
ends of the springs on the pedal when the latter is pressed down they are connected
together by a cross piece i which carries at its ends friction rollers which alone
come in direct contact with the pedal and receive the pressure, transmitting it to
the aforesaid springs. By these means the sliding friction of the springs is

page_text: transformed into the lesser rolling friction. The cross bar E connecting the
converging bars carries an angle piece I strengthened by vertical ribs, between
which are carried three rollers K and K K¹ one of which K for convenience and
clearness in the following description may be designated the primary roller, and
the other two K' K¹ secondary rollers.
This cross bar E also carries a fork in which is carried a fourth roller L. Two
other rollers M' M" carried in fixed bearings below the free ends of the pedal
serve in combination with the said Fourth roller L to guide a chain O which is
fastened to a traction wire connected with the signal devices at the preceding
apparatus. This chain O is fixed at one end at the point P and is drawn in or let
out by the movement of the pedal A. If the pedal is pressed down by the flanges
of a pair of wheels rolling over the apparatus a latch Q which may be called the
primary latch takes over the primary roller K and holds the pedal in the depressed
position until further action is required.
A prolongation upwards of the primary latch Qlays against its corresponding
primary roller K whilst two other latches Q1 Q¹ which may be called secondary
latches take an inclined position free of the secondary rollers. Springs R. R¹. R¹.
press against these three latches and preserve their relative positions when the
apparatus is at rest. The primary latch Q is so connected with a drum T by a
small chain of wire U passing over it that by turning the said drum T to the
right hand for example the said small chain or wire U is tightened and the
resistance of the spring R acting on the primary latch Q is overcome.
The two secondary latches Q¹ Q1 are each connected with the said drum by
means of a chain or wire U¹ passing under the same, so that these latter chains or
wires U¹ U¹ become slack when the wire U connected to the primary latch Q is
tightened and vice versa. The aforesaid drum T receives its motion from a
lever V to which the traction wire W connected with the moving mechanism of
the signal device at this apparatus is joined. There are thus present in connection
with each apparatus two ends O and W of traction wires. One O goes from the
apparatus to join on to the traction wire which leads towards and is connected
with the signal device at the preceding apparatus after which it joins the
corresponding drum lever V in that apparatus. The other end W produces the
connection between each two following apparatuses and joins on to a moveable
bar a carrying the explosive signal.
The action of the apparatuses on each other is as follows -
In order to render the action clear it will be necessary to consider at least three
such apparatuses placed behind one another, over each of which in succession a
railway train is supposed to pass. These three apparatuses will be numbered
respectively I. II. and III. and for clearness the letters of reference are furnished with
index numbers 1. 2. 3. corresponding to those numbers. It should here be under-
stood that an apparatus and the signal preceding it are to be always regarded as, in
a sense belonging to each other. W belongs to the pedal apparatus next to it and
forms the connecting link between the apparatuses which are regarded as not
belonging to each other. When the train rolls over the apparatus No. I the
pedal A' in that apparatus is pressed down, and is held fast by its primary latch Q¹
taking over its primary roller K¹. By the simultaneous depression of the chain
roller L' on the pedal A¹ the chain O and the traction wire Z' fastened thereto
are slackened and a compensating weight X' connected with it is lowered drawing
after it the traction wire Y¹ leading to the signal device belonging to apparatus
or station preceding No I. This movement is transmitted in the usual known
way to the optical and explosive signals. As regards the latter in such a manner,
that the explosive cartridge C' resting on the upward end of a bar a¹ which is
held at the side of the track when out of action by a counterweight b' is pushed
on to the rail and is thus presented to receive the pressure of the wheel.
When the train passes the apparatus No II the pedal A* in that apparatus is
pressed down and is held fast by its primary latch Q. By the simultaneous
depression of the chain roller L' with the pedal its chain O and the traction wire Z³

page_text: are slackened, a corresponding compensating weight X is lowered, and draws with
it the traction wire Y2 leading to the signal device belonging to apparatus No II
(placed beside the apparatus No. 1). By the movement of the bar as on the
upward curved end of which the explosive cartridge Crests, the chain or traction
wire W connected to the lever V₁ of the first apparatus is pulled and the said
lever turned say to the right; this turns the drum T' in that apparatus also to
the right whereby the primary latch Q' is withdrawn from its primary roller K¹ so
that the latter, and with it the pedal A¹ are released. The pedal springs G₁ then
lift the pedal so that the latter again takes its inclined position of rest.
It will be understood that the primary latch Q1 in apparatus No I is now in a
position, in which it could not lay hold of and hold fast its pedal A¹ on the passage
of a second train over the said apparatus No. I. In order to avoid this eventuality
the other or secondary latches Q1, Q¹, are so connected with the drum T by the
chains U that the said chains U₁, U, becomes slack when U is tightened and vice
versa. In the foregoing case the said secondary latches Q1, Q', influenced by their
springs R¹, R', would take over the secondary rollers K', K, and thus hold fast the
pedal A¹ in apparatus No. I when a second train passes over it.
When the pedal A¹ in apparatus No. I returns again to its inclined position of
rest its chain roller L' pulls the chain O' and thereby the traction wire leading
towards the compensation weight X¹ which is raised and thereby the traction
wire Y leading to the signal bar in the preceding apparatus is ceded to the action
of its corresponding counterweight 61 this latter draws the explosive signal the
optical signal, and the said traction wire Y¹ after it and places the whole apparatus
in the position of rest.
When the first considered train passes over No. III apparatus the pedal A³ of
the latter is pressed down and actions of the parts take place substantially the
same as those at apparatus No. II the signal devices belonging to apparatus No. III
(which are placed at apparatus No. II) are put on and those belonging to No. II
(which are placed at apparatus No. 1) are taken off. By the taking off of the
signal apparatus belonging to No. II the chain W₁ of the primary latch in
apparatus No. I is again slackened and by the action of its spring R' (which must
alone be stronger than the two springs R', R', of the secondary latches together),
the drum T is turned to the left, whereby the lever V₁ is raised and the secondary
latches QQ are drawn into the position in which they cannot take over their
corresponding secondary rollers if the pedal A¹ in No. I apparatus is pressed
down.
The apparatus No. I is thus restored to its original position of rest and its
primary latch Q1 returned into the position in which it can hold its pedal A¹ when
the latter is again pressed down. The chief parts of the moving mechanism are
placed in a case K to protect them from the weather and dust, this case is covered
by a sheet iron cover and in order to protect the pedal springs G a plate p is or
may be screwed over the converging bars D of the pedal so as to cover the said
springs.
Having now described the nature of the said improvements in self acting block
signalling apparatus, and the manner in which the same is to be performed I would
have it understood that what I claim is.
First. The combination of the pedal A with the roller L and the band chain O
leading to the rollers M¹ M" which band chain is joined to the draw wire going
to the signals as hereinbefore described and illustrated in the drawings hereto
annexed.
Second. The combination of the pedal A with the angle piece I furnished with
ribs between which are carried the rollers K and K₁ K₁ as herein before described
and illustrated in the drawings hereto annexed.
Third. The arrangement of the three latches Q and Q¹, Q¹, in combination with
the drum T which can act on the three latches by means of the chains or wires U
and U U¹ which receive their motion from the chain or wire W through the
arm V as hereinbefore described and illustrated in the drawings hereto annexed.

page_text: Fourth. The arrangement of the springs G the upper ends of which are con-
nected together by a cross piece which carries at its ends friction rollers which
bear against the pedal A as hereinbefore described and illustrated in the drawings
hereto annexed.
Fifth. The combination of the pedal apparatus with the bar a so that at the
pulling on (einstellen) of the signals the pedal is freed by means of the chain or
wire W, arm V, drum T and chain or wire U or chains or wires U U₁ as herein-
before described and illustrated in the drawings hereto annexed.
In witness whereof I the said Eugène Callot have hereunto set my band
and seal this second day of September in the year of Our Lord one
thousand eight hundred and eighty two.
T
TLOO
E. CALLOT. (L.)
(स)