Improvements in Electric Railways of the Sectional Conductor Type.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Electric Railways of the Sectional Conductor Type.
A communication from abroad by FREDERICK CARLETON ESMOND, of 488, Fourth
Street, Brooklyn, in the County and State of New York, United States of
America, Electrical Engineer.
.
I, JAMES GRIEVE LORRAIN, M.I.E.E., M.I. Mech. E., of Norfolk House, Norfolk
Street, London, W.C., Chartered Patent Agent, do hereby declare the nature of
this invention (as communicated to me from abroad) to be as follows;-
-
My present invention relates to electric railway systems in which brushes or
contact bars carried by a car make electrical connection with conducting sections
in the roadway, said sections being controlled by switches placed underneath or
near the track and so connected that as the car travels along successive switches
are closed by the action of electro-magnets so as to convey current to the section
or sections over which the car is passing at the time. Such systems of electric
railways are well known in the art.
One of the chief difficulties in connection with a railway worked on this
system is that the conducting sections are liable to remain connected electrically
to the line or source of the current after the car has passed. This constitutes a
serious danger and many devices have been designed to obviate it. My invention
secures that each switch not only controls the current passing to its corresponding
section but protects a section behind it so that in event of any one section having
been left connected to the line, the passing of the car over the section controlled
by the protecting switch automatically cuts off its connection with the line.
In the accompanying drawing I illustrate diagrammatically one way in which I
propose to carry out my invention. In this drawing I show my invention as
applied to one particular method of picking up current from conducting sections
on the roadway but my invention is also applicable to other systems of this kind.
In the drawing 1 is the main supply conductor. 2, 2, are the conducting sec-
tions in the track against which rub the brushes carried by the car conveying the
quent to the motor. I here show them in the form of parallel rails laid in
the track but my invention is not confined to the use of this particular arrange-
ment as I have already explained. Three switches A, B, and C are shown in
the drawing, each controlling one pair of sections. These switches may be placed
in any convenient position relatively to the track either by themselves in separate
switch boxes or grouped together with several other similar switches on a switch
board in a man-hole in the roadway or in any other convenient locality. Each
switch is provided with an electro-magnet with two windings as 3 and 4 and is
fitted with an armature 5 and a metallic connecting piece 6 so adjusted that when
the pick-up current is passed through the winding of the magnet the armature is
attracted and raises the connecting piece, thereby connecting the stud 7 with the
stud 8 and causing a current to pass direct from the line to the corresponding
insulated section.

page_text: I have here only briefly indicated the way of action of one of these switches and
in my drawing I have shown a double winding on the magnet but I do not attach
any importance to this particular arrangement as any pick-up switch would
serve equally well for the purpose of illustrating my invention.
As the car travels along current is sent forward through the next switch in
advance and the sections corresponding to that switch are thereby connected to
the line as will be readily understood by anyone acquainted with the art. It
will be seen that should the connecting piece remain for any cause stuck after it
has been raised by the electro-magnet and after the car has passed on, the sections
corresponding to the switch that has stuck would be left connected to the line.
Should for instance the connecting piece 6 remain stuck the stud 7 will remain
permanently connected to the stud 8 and the corresponding sections 2, 2 will
remain permanently connected to the line and would thereby be a source of danger.
It is to overcome this difficulty that I have designed the device which consti-
tutes the present invention, which I will now proceed to describe.
I provide each switch with a second armature (shown as an upper armature in
the drawing) so arranged that when the electro-magnet is excited the said second
armature is attracted at the same time as the first armature and electrical con-
nection made between two studs such as 15 and 9 in switch C. When not so
attracted, a spring or similar device forces the upper armature into the position
shown in the figure. The studs are connected as follows:-One stud 15 is con-
nected direct to the ground at 16 while the other stud 9 is connected to a stud 10
in the second switch (switch A) behind the switch C. This stud 10 is so placed
that when the connecting piece 6 is raised, electrical connection is made between
the two 7 and 10. It will be seen that should the connecting piece 6 of switch A
stick, as soon as the magnet of switch C has been excited by the onward passage
of the car, the upper armature of switch C will be attracted and will make electrical
connection between the line, studs 7, 10, 9 and 15, and ground.
If
I provide a fuse, such as 11, in the circuit connecting each switch with the
line and which is blown when the upper armature of switch C and the lower
armature of switch A are both in the attracted position at the same time.
therefore the lower armature of any switch should happen to stick the fuse of that
switch will be blown by the upper armature of the switch two sections ahead, the
result being that the switch whose armature has stuck is completely cut off from
the line. My invention therefore provides absolute protection against any section
remaining connected to the line after the car has passed.
I have herein referred to one section or switch being ahead of another. In
using that expression I refer to the movement of the car and assume that a double
line of rail is being used. In that case there may of course be two complete
sets of switches, one to control the sections on the "
"
up line and the other to S
control the sections on the "down" line. In cases where a single track only is
being used I can utilise my invention by connecting each switch with the upper
armature not only of the switch two sections distant from it in one direction but
also two sections distant from it in the other direction. Thus in the drawing
the stud 12 in switch C would not only be connected to the upper armature of 4
the switch two sections to the right of it but also to the stud 13 in the switch A so
that if the car is moving from left to right C will protect A. If the car is going
from right to left A will protect C.
I may sometimes connect the lower contact piece of each switch, when not in use,
with the ground by making it touch a stud such as that shown at 14 in switch A.
This device may be useful in certain cases by earthing the lower contact piece
of any switch when not in use, as a security against leakage across the switch.
The protective action of my switch is not impaired when its own fuse has been
blown in consequence of the sticking of its lower connecting piece. For instance,
suppose that the said connecting piece of switch B in the figure had stuck and 5
its fuse blown by the protective action of the switch two sections to the right of B,
then B would still continue to protect the switch two sections to the left of B,

page_text: for its protective action depends upon the working of its electro-magnet which
is effected by the picking up current supplied from A through the brushes under
the car, A being assumed to be in good order.
In cases where the switches for a number of sections are grouped on a switch
board placed in a man-hole I sometimes arrange that the last switch on the switch
board, that is, the switch controlling the last section of the line connected to the
switch board, shall cut out the bus-bar of the whole series of switches on the
switch board, so that if by any means whatever any one of the sections controlled
by the man-hole has been left connected to the line, the last switch on the switch
board will cut it out.
Datel th
ALL. T
T
1000
i always of the Sectional Conductor Type.
A communication from abroad by FREDERICK CARLETON ESMOND, of 488, Fourth
Street, Brooklyn, in the County and State of New York, United States of
America, Electrical Engineer.
I, JAMES GRIEVE LORRAIN, M.I.E.E., M.I. Mech. E., of Norfolk House, Norfolk
Street, London, W.C., Chartered Patent Agent, do hereby declare the nature of
this invention (as communicated to me from abroad) and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement:-
My present invention relates to electric railway systems in which bruslies or
contact bars carried by a car make electrical connection with conducting sections
in the roadway, said sections being controlled by switches placed underneath or
near the track and so connected that as the car travels along successive switches
are closed by the action of electro-magnets so as to convey current to the section
or sections over which the car is passing at the time. Such systems of electric
railways are well known in the art.
One of the chief difficulties in connection with a railway worked on this
system is that the conducting sections are liable to remain connected electrically
to the line wire or source of the current after the car has passed. This constitutes a
serious danger and many devices have been designed to obviate it. My invention
secures that each switch not only controls the current passing to its corresponding
section but protects a section behind it so that in the event of any one section
having been left connected to the line, the passing of the car over the section
controlled by the protecting switch automatically cuts off its connection with the
line.
In the drawings left with the Provisional Specification I illustrate diagram-
matically one way in which I carry out my invention. In this drawing I show
my invention as applied to one particular method of picking up current from
conducting sections on the roadway but my invention is also applicable to other
systems of this kind.
In the drawing, 1 is the main supply conductor. 2, 2 are the conducting
sections in the track against which rub the brushes carried by the car conveying
the current to the motor. I here show them in the form of parallel rails laid in
the track but my invention is not confined to the use of this particular arrange-
ment as I have already explained. Three switches A, B and C are shown in the

page_text: diawing, each controlling one pair of sections. These switches may be placed in
any convenient position relatively to the track either by themselves in separate
switch boxes or grouped together with several other similar switches on a switch
board in a manhole in the roadway or in any other convenient locality. Each
switch is provided with an electro-magnet with two windings as 3 and 4 and is
fitted with an armature 5 and a metallic connecting piece 6 so adjusted that when
the pick-up current is passed through the winding of the magnet the armature
is attracted and raises the connecting piece, thereby connecting the stud 7 with
the stud 8 and causing a current to pass direct from the line 1 to the corresponding
insulated section.
I have here only briefly indicated the way of action of one of these switches
and in my drawing I have shown a double winding on the magnet but I do not
attach any importance (in so far as my present invention is concerned) to this
particular arrangement in itself as any pick-up switch would serve equally well
for the purpose of illustrating my invention.
As the car travels along current is sent forward through the next switch in
advance and the sections corresponding to that switch are thereby connected to
the line as will be readily understood by anyone acquainted with the art. It will
be seen that should the connecting piece remain for any cause stuck after it has
bern raised by the electro-magnet and after the car has passed on, the sections
corresponding to the switch that has stuck would be left connected to the line.
Should for instance the connecting piece 6 remain stuck the stud 7 will remain
permanently connected to the stud 8 and the corresponding sections 2, 2 will
remain permanently connected to the line and would thereby be a source of danger.
It is to overcome this difficulty that I have made my present invention, which I
will now proceed to describe.
I provide each switch with a second armature (shown as an upper armature in
the drawing) so arranged that when the electro-magnet is excited the said second
armature is attracted at the same time as the first armature and electrical con-
nection made between two studs such as 15 and 9 in switch C. When not so
attracted, a spring or similar device forces the upper armature into the position
shown in the figure. The studs are connected as follows:-One stud 15 is con-
nected direct to the ground at 16 while the other stud 9 is connected to a stud 10
in the second switch (switch A) behind the switch C. This stud 10 is so placed
that when the connecting piece 6 is raised electrical connection is made between
the two studs 7 and 10. It will be seen that should the connecting piece 6 of
switch A stick, as soon as the magnet of switch C has been excited by the onward
passage of the car, the upper armature of switch C will be attracted and will make
lectrical connection between the line, studs 7, 10, 9 and 15, and ground.
I provide a fuse, such as 11, in the circuit connecting each switch with the line
and which is blown when the upper armature of switch C and the lower armature
of switch are both in the attracted position at the same time. If therefore the
lower armature of any switch should happen to stick the fuse of that switch will
be blown by the upper armature of the switch two sections ahead, the result being
that the switch whose armature has stuck is completely cut off from the line.
My invention therefore provides absolute protection against any section remaining
connected to the line after the car has passed.
In
I have herein referred to one section or switch being ahead of another.
using that expression I refer to the movement of the car and assume that a
double line of rails is being used. In that case there may of course be two com-
plete sets of switches, one to control the sections on the "up" line and the other to
control the sections on the "down" line. In cases where a single track only is
being used I can utilize my invention by connecting each switch with the upper
armature not only of the switch two sections distant from it in one direction but
also two sections distant from it in the other direction. Thus in the drawing the
stud 12 in switch C would not only be connected to the upper armature of the
switch two sections to the right of it but also to the stud 13 in the switch A so

page_text: that if the car is moving from left to right C will protect A. If the car is going
from right to left A will protect C.
I may sometimes connect the lower contact piece of each switch, when not in
use, with the ground by making it touch a stud such as that shown at 14 in
switch A. This device may be useful in certain cases by earthing the lower
contact piece of any switch when not in use, as a security against leakage across
the switch.
The protective action of my switch is not impaired when its own fuse has been
biown in consequence of the sticking of its lower connecting piece. For instance,
suppose that the said connecting piece of switch B in the figure had stuck and
its fuse blown by the protective action of the switch two sections to the right of B,
then B would still continue to protect the switch two sections to the left of B, for
its protective action depends upon the working of its electro-magnet which is
effected by the picking up current supplied from A through the brushes under
the car, A being in good order.
In cases where the switches for a number of sections are grouped on a switch
board placed in a manhole I sometimes arrange that the last switch on the switch
board, that is, the switch controlling the last section of the line connected to the
switch board, shall cut out the bus-bar of the whole series of switches on the
switch board, so that if by any means whatever any one of the sections controlled
by the manhole has been left connected to the line, the last switch on the switch
board will cut it out.
It will be seen that the details of my invention may be varied to a considerable
extent without departing from the spirit of my invention.
Having now particularly described and ascertained the nature of this inven-
tion (as communicated to me from abroad) and in what manner the same is to be
performed, I declare that what I claim is:
-
1. The method of preventing sticking of the switches substantially as set forth.
2. The arrangement and combination of parts for preventing sticking of the
switches substantially as set forth.
3. The combination of switch magnet and double armature (or armature lever)
substantially as and for the purpose set forth.
4. The improvement which consists in breaking the circuit through the magnet
of a sticking supply switch by causing a fuse in the supply lead of that switch
to be blown by providing an easier path to earth through another of the supply
switches (or part thereof).
Dated this 4th day of October 1899