Improvements in Crossings of Electric Conductors for Electric Railways and Tramways.
Year: 1896

page_text: Date of Application, 12th Aug., 1896
Complete Specification Left, 12th May, 1897-Accepted, 12th June, 1897
PROVISIONAL SPECIFICATION.
Improvements in Crossings of Electric Conductors for Electric
Railways and Tramways.
We ALBION THOMAS SNELL Consulting Engineer, of Suffolk House, Cannon
Street, in the City of London, CHARLES EDWARD GROVE, Electrical Engineer,
of 11 Cawley Road, South Hackney in the County of Middlesex, and ARNOLD
FRANK HILLS Managing Director of The Thames Iron Works and Ship Building
Co. Ld. of Blackwall in the County of Middlesex, do hereby declare the nature
of this invention to be as follows:-
In electric railways, or tramways, to which the electric energy for propelling
the trains, or vehicles, is supplied upon the "three wire" system, usually with the
rolling metals as the middle conductor, the traius or vehicles, running upon one
pair of rails, say upon the "up" side will be taking current from, say, the positive
side of the system while the trains, or vehicles, running on the other, or "down,"
rails, will be taking current from the other, say, the negative side of the system =
and the object of this invention is to obviate the use of a "dead" section and its
attendant disadvantages, by providing means whereby the trains, or vehicles, may
pass from one side of the electrical system to the other without any risk of making
a contact, or short circuit, between the main outer electric conductors. We also
include herein the use of alternate positive and negative sections on the up or
down lines if desired.
According to this invention we use a short length of bare conductor (which we
may term the "crossing conductor ") insulated from earth and connected either
permanently or through a switch to one of the outer conductors of the system and
extending across the rolling metal crossings and points and for a certain distance
at each end extending parallel to the rolling metals on each side of the crossings
to obviate any dead length.
If the working conductors forming the two outer conductors of the system be
laid at a lower level than the trains or vehicles either between the metals or along-
side of them, then the crossing conductor should be erected overhead above the
trains or vehicles, and vice versa. This arrangement ensures that the crossing
conductor is maintained at a safe distance from the outer conductor of opposite
polarity, and that the crossing conductor is in a different horizontal plane from
that of the working conductors, so that there is no risk of accidental contact
between the two. The working conductors forming the two outer conductors can
be kept throughout severally either between the ways forming the "up" and
"down" lines, or else outside the two lines. The working conductors are thus
always separated by at least the distance between the two lines of metals, so that
accidental contact between them is prevented and plate-layers and others can walk
along the line without any risk of electric shock.
On the locomotive, or motor-car, there are two sets of contact brushes, or rolling, or
rubbing, contacts, to collect current respectively from the working conductors and the
crossing conductors. A two-way switch is provided so that the two sets of brushes, or
contacts, cannot be in electric contact with the motor, or motors, at the same time.
Power is thus supplied from the top, or bottom, conductor according to the position
at which the switch is set.

page_text: The two-way switch may be actuated by hand, the driver making the necessary
changes as the vehicle passes the points, or, it may be made to work automatically
for example by the momentum of the vehicle operating stops arranged to shift the
movable contact piece of the two-way switch. The crossing conductor may also
be placed in electric connection with one of the outer conductors automatically,
when the vehicle is entering the leading points, and disconnected when leaving the
trailing points. This may be done for example by the momentum of the train
operating stops arranged to close a switch.
If the working conductors be laid beneath the vehicles insulating guards will of
course be provided in the neighbourhood of the points and crossings of the rolling
metals to prevent the lower brushes or contacts from putting the rolling metals,
forming the middle conductor of the system, into electric contact with the working
conductor as the train or vehicle passes the points.
If the working conductors be placed overhead, the crossing conductor then
being below, must be protected from contact with the rolling metals, and means
must be provided, as above mentioned, to prevent the lower brushes, or
contacts from putting the rolling metals into electric contact with the crossing
conductor.
Dated this 12th day of August 1896
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
Improvements in Crossings of Electric Conductors for Electrio
Railways and Tramways.
We, ALBION THOMAS SNELL, Consulting Engineer, of Suffolk House, Cannon
Street, in the City of London, CHARLES EDWARD GROVE, Electrical Engineer,
of 11, Cawley Road, South Hackney, in the County of Middlesex, and ARNOLD
FRANK HILLS, Managing Director of The Thames Iron Works and Ship
Building Company Limited, of Blackwall, in the County of Middlesex, do hereby.
declare the nature of this invention and in what manner the same is to bo
performed, to be particularly described and ascertained in and by the following
statement :-
Our invention relates to electric railways or tramways and especially to a novel
arrangement of the electric conductors in connection with crossings or sidings
branching from the main lines.
In electric railways or tramways to which the electric energy for propelling the
trains or vehicles is supplied upon the "three wire" system usually with the rails
of the permanent way (hereinafter referred to as the rolling metals) as the middle
conductor, the trains or vehicles running upon one pair of rails, say upon the "up'
side, will be taking current from, say, the positive side of the system, while the
trains or vehicles running on the other or "down "rails will be taking current from
other, say, the negative side of the system.
The chief object of this invention is to provide means whereby the trains or
vehicles may pass from one side of the electrical system to the other without any
risk of making a contact, or short circuit, between the main or outer electric
conductors. Our invention is also applicable for use upon railways wherein the
conductors have alternate sections of positive and negative polarity.
According to this invention we use a short length of bare conductor (which we
may term the "crossing conductor ") insulated from earth and connected, either
permanently or through a switch, to one of the outer conductors of the system and

page_text: extending across the rolling metal crossings and points and for a certain distance
at each end extending parallel to the rolling metals on each side of the crossings to.
obviate any dead length.
If the working conductors forming the two outer conductors of the system be
laid at a lower level than the trains or vehicles then the crossing conductor should
be erected overhead above the trains or vehicles, and vice verst. This arrangement
ensures that the crossing conductor is maintained at a safe distance from the outer
conductor of opposite polarity, and that the crossing conductor is in a different.
horizontal plane from that of the working conductors, so that there is no risk of
accidental contact between the two. The working conductors forming the two.
outer conductors can be kept throughout, severally, either between the ways
forming the "up " and "down," lines, or else outside the two lines. The
working conductors are thus always separated by at least the distance
between the two lines of metals so that accidental contact between them is.
prevented.
In the accompanying drawing,
Figure 1 is a plan view shewing the arrangement of conductors according to
our invention; and,
Figures 2 and 3 are side and end views respectively.
In these figures A A is one outer conductor, say of positive polarity, B B is the
other outer conductor, say of negative polarity, R R R are the rails forming.
the middle or neutral conductor, C C is the overhead conductor electrically
connected through a switch, or otherwise with either A A or B B and insulated
from earth.
Ou the locomotive or motor car there are two sets of contact brushes, or rolling
or rubbing contacts, to collect currents respectively from the working conductors
and the crossing conductors. A two-way switch is provided so that the two sets.
of brushes or contacts cannot be in electric contact with the motor or motors at the
same time. Power is thus supplied from the top or bottom conductor according to
the position at which the switch is set.
The two-way switch may be actuated by hand, the driver making the necessary
changes as the vehicle passes the points, or it may be made to work automatically,.
for example, by the momentum of the vehicle operating stops arranged to shift the
movable contact piece of the two-way switch. The crossing conductor may also
be placed in electric connection with one of the outer conductors automatically,
when the vehicle is entering the leading points, and disconnected when leaving the
trailing points. This may be done for example by the momentum of the train.
operating stops arranged to close a switch.
If the working conductors be laid beneath the vehicles insulating guards will be
provided in the neighbourhood of the points and crossings of the rolling metals to
prevent the lower brushes or contacts from putting the rolling metals, forming the
middle conductor of the system, into electric contact with the working conductor as
the train or vehicle passes the points.
If the working conductors be placed overhead, the crossing conductor then being
below must be protected from contact with the rolling metals, and means must be
provided, as above mentioned, to prevent the lower brushes or contacts from.
putting the rolling metals into electric contact with the crossing conductor.
In the drawing we have represented our invention as applied to a double
cross over road and it is to be understood that in this case both the crossing.
conductors C C are connected to the same side of the system. It will be obvious,.
however, that our invention is equally applicable where there is only a single cross
over, and also to sidings.
Having now particularly described and ascertained the nature of our said inven-.
tion and in what manner the same is to be performed, we declare that what
we claim is :-
The use at crossover roads in a three wire system of electric traction of an.

page_text: insulated crossing conductor either above or below the level of the working con-
ductors, and electrically connected (permanently or through switches) with one
side of the system, in combination with switches or the like on the locomotive or
motor car for putting the collecting brushes or contacts into connection with the
crossing conductor as the locomotive or motor car crosses from one road to the
other, substantially as described.
2012
1007
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agente for the Applicants.