Improvements in and connected with Electric Tramways or Railways, and Means for Working Electrically Propelled Vehicles thereon.
Year: 1890

page_text: Date of Application, 2nd Oct., 1890
Complete Specification Left, 2nd July, 1891-Accepted, 15th Aug., 1891
PROVISIONAL SPECIFICATION.
Improvements in and connected with Electric Tramways or
Railways, and Means for Working Electrically Propelled
Vehicles thereon.
I, EDWARD HOPKINSON D. Sc. of Salford Iron Works, Manchester in the
County of Lancaster, do hereby declare the nature of this invention to be as
follows:-
In tramways and railways upon which vehicles are propelled by electric power,
I have found that a convenient form of conductor for transmitting the electric
current to the motor, carriage, or locomotive is a continuous bar of iron or steel of
channel, tee or other section which is placed in proximity to the rails of the
permanent way for instance between them or on one side thereof and supported in
any suitable way for instance on insulators attached to the sleepers. The current
is taken off from this conductor by a collector which slides or rolls therealong.
At points for branch lines or sidings where the rails cross each other, means must
be provided to allow the collector to pass over the crossing rail without making
contact with it.
According to my invention I break the conductor and bend it parallel with the
cross rail on either side and fix the parts at such a level above the cross rail, that
the collector passes from the one section of the conductor to the other section on
the opposite side of the cross-rail without touching the latter, the collector being
of such width that it is supported on one section of the conductor before it leaves
the other. In some cases this might involve a collector of greater width than is
convenient.
In order to restrict the width of the gap between the two sections of the
conductor as much as possible and the consequent width of the collector, I may
make according to my invention the two portions of the conductor adjacent to the
rail moveable and allow them to swivel or move so that they may be brought up
close to the cross rail when the collector is crossing it, and at other times be
opened so as to leave a gap of sufficient width for the flange and tyre of the wheels
of vehicles travelling on the other line.
The moveable portions of the conductor may be conveniently actuated by the
same system of levers as the rail points or be interlocked with them, so that the
conductor is left open when the points are set for the branch line and closed when
set for the main line.
In order to secure the more certain insulation of the conductor from the rails I
may make the two sections on either side of the cross rail mechanically continuous
with the conductor, but electrically disconnected and to complete the electrical
connection by other means.
With this object it is often convenient to construct these portions of wood or
other insulating material and to provide the vehicle with two collectors arranged
so that the leading collector may make contact on the one section of the charged
conductor before the back collector leaves the other section of the charged
conductor.
To obviate the danger of an excessive flow of current if by any mishap, the
collector should make electrical contact between the rail and the conductor, I
may according to my invention, separate the portions of the conductor on either
side of the crossing at any convenient distance therefrom and connect them to the
continuous conductor through a suitable resistance so that the current in no case
could be dangerously great. When I employ such a resistance it is not essential
that the sections of the conductor adjacent to this cross rail should be raised, so as

page_text: to prevent the collector from touching the cross rail, as the amount of resistance in
circuit can be adjusted so that the current passing from the collector to the rail
cannot exceed the safe limit.
I may construct such resistances of cast iron bars arranged in the form of a grid
or zig-zag, as cast iron has a greater specific resistance than any other metal
conveniently obtainable, and can be readily cast of any section, or in any shape
convenient for the particular purpose in view. Such resistances are applicable for
the regulating resistances of electric locomotives and other vehicles propelled by
electric power.
Dated this 2nd day of October 1890
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.
COMPLETE SPECIFICATION.
Improvements in and connected with Electric Tramways or
Railways, and Means for Working Electrically Propelled
Vehicles thereon.
I EDWARD HOPKINSON D. Sc. of Salford Iron Works Manchester in the County
of Lancaster 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 :-
In tramways and railways upon which vehicles are propelled by electric power I
have found that a convenient form of conductor for transmitting the electric
current to the motor carriage or locomotive is a continuous bar of iron or steel of
channel tee or other section which is placed in proximity to the rail or rails of
the permanent way for instance between them or on one side thereof and supported
in any suitable way for instance on insulators attached to the sleepers. The
current is taken off from this conductor by a collector on the vehicle which slides
or rolls along the said conductor. At points for branch lines or sidings where the
rails cross each other means must be provided to allow the collector to pass over
the crossing rail without making contact with it.
According to my invention I break the conductor and bend it parallel with the
cross rail on either side and fix the parts at such a level above the cross rail that
the collector passes from the one section of the conducior to the other section on
the opposite side of the cross rail without touching the latter, the collector being
of such width that it is supported on one section of the conductor before it leaves
the other. In some cases this might involve a collector of greater width than is
convenient. In order to restrict the width of the gap between the two sections of
the conductor as much as possible and the consequent width of the collector I may
make according to my invention the two portions of the conductor adjacent to the
rails moveable and allow them to swivel or move so that they may be brought up
close to the cross rail when the collector is crossing it and at other times be opened
so as to leave a gap of sufficient width for the flange and tyre of the wheels of
vehicles travelling on the other line.
The moveable portions of the conductor may be conveniently actuated by the
same system of levers as the rail points, or be interlocked with them so that the
conductor is left open when the points are set for the branch line and closed when
set for the main line.
In order to secure the more certain insulation of the conductor from the rails I
may make the portions of the conductor on either side of the cross rail mechanically
but not electrically continuous with the adjacent portions of the conductor and
complete the electrical connection by other means.. This may be done by making
the parts which mechanically but not electrically continue the line of the conductor
of wood or other insulating material and providing the vehicle with two collectors
arranged so that the leading collector may make contact on the one section of the

page_text: charged conductor before the back collector leaves the other section of the charged
conductor.
To obviate the danger of an excessive flow of current if by any mishap the
collector should make electrical contact between the rail and the conductor I may
according to my invention separate the portions of the conductor on either side of
the crossing at any convenient distance therefrom and connect them to the con-
tinuous conductor through a suitable resistance so that the current in no case could
be dangerously great. Where 1 employ such a resistance it is not essential that
the sections of the conductor adjacent to this cross rail should be raised so as to
prevent the collector from touching the cross rail as the amount of resistance in
circuit can be adjusted so that the current passing from the collector to the rail
cannot exceed the safe limit.
I may construct such resistances of cast iron bars arranged in the form of a grid
or zig zag as cast iron has a greater specific resistance than any other metal
conveniently obtainable and can be readily cast of any section or in
convenient for the particular purpose in view.
any shape
In order that my invention may be more fully understood I will now proceed
more particularly to describe the same and for that purpose shall refer to the several
figures of the annexed drawings in which Figure 1 is a transverse section of a line
shewing the conductor a placed between the rails of the permanent way. I have
shewn the conductor a of channel section but it may be flat, angle, tee, or any other
convenient section.
The conductor a is also shewn supported by insulators c carried on the main
sleepers d and placed between the rails of the permanent way and with its
upper surface slightly below the top of the rails but it may be supported by any
other suitable means and be placed on one side of either of the rails and at a level
different from that shewn or otherwise in proximity thereto.
It may
The current is taken off from this conductor by means of a collector e which
slides or rolls on the conductor a. At crossings or other parts of the line where
the rails cross each other the continuity of the conductor must be broken so as to
clear the rails 61 62 and means must be provided to allow the collector to pass over
the crossing rail without making contact with it. The arrangement which I
provide for this purpose is shewn in plan in Figure 2. The conductor a is broken
and its ends may be bent parallel to the cross rail and raised to a convenient height
above it so that the collector moving along the surface of the conductor is raised
above the level of the cross rail and passes from one section of the conductor to
the other without touching the cross rail. It is necessary for this purpose that
the collector should be somewhat wider than the tyre of the wheel so that the said
collector may not fall into the gap between the sections of the conductor.
sometimes happen that the gap thus left may be so wide as, if the ends of the
conductor be fixed, to require a collector of inconvenient width. In order to
reduce this width one or both of the end portions of the conductor a adjacent to
the rails may be made moveable and be allowed to swivel so that when the
collector is about to pass over them they may be brought close up to the rail and
at other times be open so as to leave a sufficient gap for the wheel to pass, this
arrangement is shewn in Figure 4. It may in some cases be convenient to make
one end of the conductor only moveable and to allow this to pass over the top of
the permanent way rails b' without touching it and make contact with the other
end of the fixed conductor. By means of such a bridge I secure the mechanical
and also if I wish the electrical continuity of the conductor when the collector has
to pass over it. Figure 3 illustrates this arrangement in which c represents the
moveable bridge or swivelling part of the conductor. This bridge may be of any
convenient shape and is not necessarily of the same section as the conductor.
If it is desirable to increase the insulation of the conductor from the rails I may
cut off the ends of the conductor some distance from the rails b' or 62 as shewn in
Figure 5 and replace them by pieces of wood for other insulating material, which
may be made moveable or arranged so as to form a bridge as already described,

page_text: I then complete the electrical connection of the two portions of the conductor by
other means.
The vehicle: is, then: provided with two collectors so arranged that the leading
collector: makes contact on the portion a¹ of the charged conductor before the
trailing: collector leaves the portion a². In order to obviate the danger of. an
excessive flow of current should the collector by any accident make electrical con-
nection between therrail and conductor I may separate the portions of the conductor
on either sides of the crossing from the continuous conductor at any convenient
distance and connect them thereto through a suitable resistance so that in no case
can the current be dangerously great.
One method of performing this is shewn in Figure 6 where the conductor a on
each side of the crossing rail is shewn broken at g the electrical connection between
this portion of the continuous conductor being made through the resistance R.
When I employ this arrangement it is not necessary to raise the conductor
above the rail to prevent the collector touching the latter as the amount of the
resistance R may be so adjusted that the current passing from. the collector.to the
rail cannot exceed a safe limit.
Having now particularly described the nature of my said invention and in
what manner the same is to be performed I declare that what I claim is :-
-
1. In tramways or railways upon which vehicles are propelled by electric power
and where the conductor is placed in proximity to the rail or rails a conductor
discontinued at the cross line and there situated at a higher level than the said
line so that the collector can pass from the conductor on one side to the conductor
on the opposite side of the said line without touching, it substantially as herein-
before explained:
2. In tramways or railways upon which vehicles are propelled by electric power
and where the conductor is placed in proximity to the rail or rails a conductor
discontinued at the cross line and at its ends at the cross line bent or situated in
the direction of the cross lin and at a higher level than the said line so that the
collector can pass from the caductor on one side to the conductor on the opposite
side of the said line withou ouching it substantially as hereinbefore described.
3.. In an arrangements has is claimed by the first or the second claiming
clauses making one or both Is of the conductor moveable substantially as and for
the purpose herein before cribed.
4. In an arrangement
clauses replacing the po
insulating material subs
'
ch as is claimed under the first second or third claiming
ns of the conductor at opposite sides of the cross line by
Lially as and for the purpose hereinbefore described.
5. In tramways or railways pon which vehicles are propelled by electric power
and where the conductor is ..aced in proximity to the rail or rails and is discon-
tinued at the cross line to allow it to cross, the electrical separation of the portions
of the conductor on t' opposite sides of the cross line and connecting them to the
continuous conduct arough a suitable resistance substantially as and for the
purpose hereinbefore described.
Dated this 2nd day of July 1801