An Improvement in Electric Railway Signals.
Year: 1890

page_text: Date of Application, 18th Mar., 1890
Complete Specification Left, 7th Jan., 1891-Accepted, 7th Feb., 1891
PROVISIONAL SPECIFICATION.
An Improvement in Electric Railway Signals.
I, ALEXANDER SIEMENS, of 12 Queen Anne's Gate, Westminster, in the County
of Middlesex, Civil Engineer, do hereby declare the nature of this invention to
be as follows:-
Automatic railway signal apparatus worked by electric currents, such as the
apparatus described in the Specification to my Patent No. 15,921 of 1888 may be
combined in such a manner that two or more signals require to be brought into
danger position before another signal can be brought into the "line clear
position.
"
According to my present invention I effect such combination of signals by the
employment of an auxiliary signal apparatus constructed and operating as follows.
I arrange two solenoids in combination with one iron core in such manner that
when a current passes through the one solenoid so as to attract the core, the latter
remains in this position even after the said solenoid ceases to be excited, until the
second solenoid is excited, when the core will be moved thereby into a second
position in which it at the same time breaks the circuit of such second solenoid.
In the first named position of the core it effects the closing of a local circuit,
which starts from a contact made by a train when this is about to enter the section
protected by the signal, thence passes through certain other conflicting signals pro-
vided they are in the danger position, in which they make the requisite contacts,
then through the second above mentioned solenoid and into the signal of this
apparatus effecting the lowering of the same, to "line clear."
The effect of employing the auxiliary signal apparatus or relay is therefore, that
the signal in connection with it is only lowered when the train is about to enter the
section and when all conflicting signals are < at danger."
33
When applying this apparatus at a junction, the " entering contact is not
actuated by the train depressing a rail, but several such contacts are provided, cach
corresponding with one of the lines of rails diverging at the junction, the one or
other of which is actuated by suitable means according to the destination of the
approaching train. The contacts may for instance be effected by permanent pro-
jections on the engines when each engine has always to go to the same destination,
or they may be effected by levers under the control of the engine driver, so that
he can select the line of the junction along which he wishes to run his train by
effecting the particular contact by means of the corresponding lever.
The signals at the junction may be worked in conjunction with the levers moving
the points, so that the electric current is made to move over the points before the
signal is lowered, or in cases where the levers are worked by hand, the electric
signals may be interlocked with them in any well known manner.
Dated this 18th day of March 1890.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improvement in Electric Railway Signals.
I, ALEXANDER SIEMENS, of 12 Queen Anne's Gate, Westminster, in the County
of Middlesex, Civil 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:-
Automatic railway signal apparatus worked by electric currents such as the

page_text: apparatus described in the Specification to my Patent No. 15,921 of 1888 may be
combined in such a manner that two or more signals require to be brought into
"danger position before another signal can be brought into the line clear'
position.
"
According to my present invention, I effect such combination of signals by the
employment of an auxiliary signal apparatas constructed and operating as follows.
arrange two solenoids in combination with one iron core in such manner that,
when a current passes through the one solenoid so as to attract the core, the latter
remains in this position even after the said solenoid ceases to be excited, until the
second solenoid is excited, when the core will be moved thereby into a second
position, in which it at the same time breaks the circuit of such second solenoid.
In the first named position of the core it effects the closing of a local circuit,
which starts from a contact made by a train when this is about to enter the section
protected by the signal, thence passes through certain other conflicting signals pro-
vided they are in the danger position, in which they make the requisite contacts,
then through the second above mentioned solenoid and into the signal of this
apparatus, effecting the lowering of the same to "line clear."
The effect of employing the auxiliary signal apparatus or relay is therefore that
the signal in connection with it is only lowered when the train is about to enter the
section and when all conflicting signals are at "danger."
When applying this apparatus at a junction, the "entering" contact is not
actuated by the train depressing a rail, but several such contacts are provided each
corresponding with one of the lines of rails diverging at the junction, the one or
other of which is actuated by suitable means, according to the destination of the
approaching train. The contacts may, for instance, be effected by permanent pro-
jections on the engines when each engine has always to go to the same destination,
or they may be effected by levers under the control of the engine driver, so that he
can select the line of the junction along which he wishes to run his train by effecting
the particular contact by means of the corresponding lever.
The signals at the junction may be worked in conjunction with the levers moving
the points, so that the electric current is made to move over the points before the
signal is lowered, or, in cases where the levers are worked by hand, the electric
signals may be interlocked with them in any well known manner.
On the
The accompanying drawing is a section of the casing containing an auxiliary
signalling apparatus or relay according to my invention shewn partly in clevation.
On an axis A is pivotted an arm B carrying a semicircular bar of soft iron.
On the base D are fixed the two solenoids E and F into the hollow interiors of
which the ends of the bar Center and in which they can freely move.
axis A is fixed a rotary switch or commutator G against which bear springs K,
the periphery against which they bear being partly of conducting material and
partly of non-conducting material so that contacts with the springs are made or
broken according to the position of the bar C. On the axis A there may be several
sets of commutators G and springs such as H K according to the conditions of the
signalling circuits to which the relay is applied.
When one of the solenoids, for instance E, is excited by an electrical current
passing through its coil, the one end of the bar C is attracted as a core into it, and
as, in this movement, its centre of gravity passes the vertical line of its axis, it
remains, like a tumbling weight, in the position to which it is attracted after the
solenoid E ceases to be excited. But, when the other solenoid F is excited the
other end of the bar C is attracted into it, and the bar tumbles to the other side and
remains there after ceases to be excited until E is, excited again.
By preference, the current of each of the two solenoids E and F is arranged in
connection with the commutator G and springs HK in such a manner that when
the bar C is made to tumble over to either side, the circuit of the solenoid which
attracted it to that side is opened, and the circuit of the other solenoid is closed,
ready to act when a current is transmitted through it..

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
An auxiliary signal apparatus or relay consisting of two vertical solenoids and
a semicircular iron bar pivotted between them on an axis carrying a commutator
arranged and operating, substantially as described.
Dated this 7th day of January 1891
ABEL & IMRAY,
Agents for the Applicant.