Method of Supplying Electrical Energy to Motor Vehicles from Two Overhead Conductors.
Year: 1899

page_text: Date of Application, 31st Jan., 1899
Date of Application, 31st Jan., 1899
Complete Specification Left, 14th Oct., 1899-Accepted, 16th Nov, 1899
PROVISIONAL SPECIFICATION.
Method of Supplying Electrical Energy to Motor Vehicles from Two
Overhead Conductors.
We, SIEMENS BROTHERS & Co. LIMITED, of 12, Queen Anne's Gate, West-
minster, in the County of London, Electrical Engineers, do hereby declare the
nature of this invention (as communicated to us from abroad by Siemens &
Halske, Aktien Gesellschaft of No. 94, Markgrafen Strasse, Berlin, S.W., in
the Empire of Germany, Electrical Engineers,) to be as follows:-
When the electrical energy is supplied to the motor vehicles of an electric
railway or tramway by means of two overhead conductors which supply currents
of different sign, the arrangements of the conductors at the points and crossings
offer considerable difficulties, as conductors with currents of different potentials
have to cross each other.
The present invention has for its object to obviate these difficulties; it con-
sists main in employing as current collectors for the two conductors respectively
a sliding bar contact and a roller contact. In this case the conductor on which
the contact roller runs and which is arranged above the other one, can pass
through without a break while the second and lower conductor over which the
contact bar slides can be interrupted for short distances at points where it
crosses the conductor with roller contact of a crossing line, without danger
of its current collector being thrown off. In crossings at an acute angle, the
current collector will not even break contact with the conductor as will be
presently shewn,
The two current collectors can be arranged on the vehicle either side by side
or one behind the other; the only precaution required to be taken being to
prevent the simultaneous contact of the contact bar with both conductors. We
will describe the invention with reference to the accompanying diagrammatic
drawing, which shews a motor vehicle A having for its two current collectors
a contact bar B and a contact roller C. D, E, and D', E¹ are the current
supply conductors of two crossing lines of an electric railway or tramway.
The conductors with currents of the same sign lie in one and the same hori-
zontal plane, and the lower ones 1) D' have the bar contact B passing over
them while the upper ones E E have the roller contact passing over them.
Although the general height of the conductors above the rails is optional, yet
it is advisable to arrange them at such a height at the points and crossings
that the arm of the bar conductor is nearly in an upright position.
The upper conductors E El are carried through unbroken, as shewn, so that
no interruption in the supply of current from these takes place.
The lower conductors on the other hand are interrupted for a short
distance (about equal to the width of a contact roller), the two parts being
connected by a suitably supported conducting bridge piece, as shewn, through
which the crossing upper conductor E or E¹ passes.
· This arrangement is possible because the contact bar cannot get displaced

page_text: relatively to its conductor on passing the gap, nor can it rise sufficiently to make
contact with the crossing conductor E or E' if it is kept in the nearly per-
pendicular position as described.
When the crossings are at right angles, the contact is of course
broken but only for al short time, but when the crossing is at
an acute angle, even such interruption of the contact can be pre-
vented by extending the ends of the conductor on either side of the
gap in a direction parallel to the crossing conductor E or E¹ to a distance equal
to about half the length of the contact bar. In this case it will be seen that
before the contact bar has left the one extension it will have already made
contact with the second extension d², so that there is no breaking of contact.
It should be observed that the crossing angle of the conductors need not agree
with that of the rail-crossing. Also, that if the rails are also used as conductors,
which for example is necessary when rotary phase currents are employed, the
motor car when breaking contact with the overhead conductors, would still be
actuated by the rail current.
It will be evident that in place of a roller contact for the conductors E E
a sliding contact shoe might be employed, the bridge connections of the con-
ductors D D being made of sufficient width for it to pass through.
ABEL & IMRAY,
Agents for the Applicants.
Method of Supplying Electrical Energy to Motor Vehicles from Two
Overhead Conductors.
We, SIEMENS BROTHERS & Co. LIMITED, of 12, Queen Anne's Gate, West-
minster, in the County of London, Electrical Engineers, do hereby declare the
nature of this invention (as communicated to us from abroad by Siemens &
Halske Aktien Gesellschaft, of No. 94, Markgrafen Strasse, Berlin, S.W.,
the Empire of Germany, Electrical Engineers,) and in what manner the same is
to be performed to be particularly described and ascertained in and by the
following statement:-
111
When the electrical energy is supplied to the motor vehicle of an electric
railway or tramway by means of two overhead conductors which supply currents
of different sign, the arrangements of the conductors at the points and crossings
offer considerable difficulties, as conductors with currents of different potentials
have to cross each other.
The present invention has for its object to obviate these difficulties; it con-
sists mainly in employing as current collectors for the two conductors respectively
a sliding bar contact and a roller contact. In this case the conductor on which
the contact roller runs and which is arranged above the other one, can pass
through without a break while the second and lower conductor over which the
contact bar slides can be interrupted for short distances, at points where it
crosses the conductor with roller contact of a crossing line, without danger
of its current collector being thrown off. In crossings at an acute angle, the
current collector will not even break contact with the conductor as will be
presently shewn.
The two current collectors can be arranged on the vehicle either side by side
or one behind the other; the only precaution required to be taken being to

page_text: prevent the simultaneous contact of the contact bar with both conductors. We
will describe the invention with reference to the diagrammatic drawing accom-
panying our Provisional Specification which shews a motor vehicle A having
for its two current collectors a contact bar B and a contact roller C; D, E, and
D, E are the current supply conductors of two crossing lines of an electric rail-
way or tramway. The conductors with currents of the same sign lie in one and
the same horizontal plane, and the lower ones D D have the bar contact B passing
over them while the upper ones E E' have the roller contact passing over them.
Although the general height of the conductors above the rails is optional, yet
it is advisable to arrange them at such a height at the points and crossings
that the arm of the bar conductor is nearly in an upright position.
The upper conductors are carried through unbroken, as shewn, so that
no interruption in the supply of current from these takes place.
The lower conductors on the other hand are interrupted for a short
distance (about equal to the width of a contact roller), the two parts being
connected by a suitably supported conducting bridge piece, as shewn, through
which the crossing upper conductor E or E' passes.
This arrangement is possible because the contact bar cannot get displaced
relatively to its conductor on passing the gap, nor can it rise sufficiently to make
contact with the crossing conductor E or E' if it is kept in the nearly per-
pendicular position as described.
When the crossings are at right angles, the contact is of course
broken but only for a short time, but when the crossing is at
2011 acute angle, even such interruption of the contact can be pre-
vented by extending the ends of the conductor on either side of the
gap in a direction parallel to the crossing conductor E or E¹ to a distance equal
to about half the length of the contact bar. In this case it will be seen that
before the contact bar has left the one extension it will have already made
contact with the second extension ², so that there is no breaking of contact.
It should be observed that the crossing angle of the conductors need not agree
with that of the rail-crossing. Also, that if the rails are also used as conductors,
which for example is necessary when rotary phase currents are employed, the
motor car when breaking contact with the overhead conductors, would still be
actuated by the rail current.
It will be evident that in place of a roller contact for the conductors E E
a sliding contact shoe might be employed, the bridge connections of the con-
ductors D D¹ being made of sufficient width for it to pass through.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what
we claim is:
In supplying electrical energy to motor vehicles from two overhead conductors
at the crossing of two lines, the method of arranging the upper conductor of
cach line to run uninterruptedly through the crossing while the lower conductor
of each line is interrupted, and has its parts connected by a looped connecting
piece, within which is the upper conductor of the crossing line, the collecting
device for the upper conductor on the vehicle being a contact roller or sliding
truck that can pass through the said loop of the lower conductor while the
collecting device for the latter is a contact bar, substantially as and for the
purpose described.
Dated this 14th day of October 1899.